From joe at joeshaw.org  Tue Oct  3 14:59:03 2017
From: joe at joeshaw.org (Joe Shaw)
Date: Tue, 3 Oct 2017 14:59:03 -0400
Subject: [CentralOH] 
	=?utf-8?q?2017-09-28_=E9=81=93=E5=A0=B4_Scribbles_?=
	=?utf-8?b?76SY5pu4L+aDoeaWhz8gcmVjdXJzaXZlIHByaW1lIHNlYXJjaDsgd2F0?=
	=?utf-8?q?ching_refactoring=3B_coming_events?=
In-Reply-To: <20170929172336.038a6643.jep200404@columbus.rr.com>
References: <20170929172336.038a6643.jep200404@columbus.rr.com>
Message-ID: <CAOxvq7zW=6xkh-7sDaOx6MEDT9HZX5BWHsnSXjr-K_pbdhR3LA@mail.gmail.com>

Oooh, sharing .gitconfig aliases is my favorite.  Mine:

[alias]
        find = !sh -c 'git ls-files | grep --color=auto -i "$@" | less
-FRSX' -
        fixup = "!f() { TARGET=$(git rev-parse "$1"); git commit
--fixup=$TARGET ${@:2} && EDITOR=true git rebase -i --autostash
--autosquash $TARGET^; }; f"
        squash = "!f() { TARGET=$(git rev-parse "$1"); git commit
--squash=$TARGET ${@:2} && git rebase -i --autostash --autosquash $TARGET^;
}; f"
        ri = rebase --interactive --autosquash --autostash
        lt = log --graph --pretty=changes
        ll = log --numstat --pretty=changes
        ds = diff --staged
        dw = diff --word-diff
        ego = shortlog -s -n --no-merges
        pr = pull-request
        rbs = !git for-each-ref --sort=committerdate
--format='%(refname:short) * %(authorname) * %(committerdate:relative)'
refs/remotes/ | column -t -s '*'
        undo = reset HEAD^
        fpr = "!f() { git fetch origin pull/$1/head:pr-$1; git checkout
pr-$1; }; f"
        append = commit --amend --no-edit
        reword = commit --amend --reedit-message HEAD
        reauthor = commit --amend --no-edit --reset-author

[pretty]
        changes = format:%Cred%h%Creset -%C(yellow)%d%Creset %s
%Cgreen(%cr) %C(bold blue)<%an>%Creset

Joe


On Fri, Sep 29, 2017 at 5:23 PM, <jep200404 at columbus.rr.com> wrote:

> https://github.com/joseph-albrecht/Project-Euler
> https://github.com/joseph-albrecht/Project-Euler/blob/
> master/Problem%203%20-%20Largest%20Prime%20Factor.ipynb
>
> doj at sbc:~$ cat .gitconfig
> ...
>
> [alias]
>         co = checkout
>         ci = commit
>         st = status
>         br = branch
>         hist = log --pretty=format:\"%h %ad %s%d [%an]%n%P parents%n%T
> tree%n\" --graph --date=iso
>         hist = log --pretty=format:\"%h %ad %s%d [%an]%n\" --graph
> --date=short
>         hist = log --pretty=format:\"%h %ad %cd %s%d [%an]%n\" --graph
> --date=iso-local
>         hist = log --pretty=format:\"%h %ad %s%d [%an]\" --graph
> --date=iso-local
>         hist = log --pretty=format:\"%h %ad %s%d [%an]\" --graph --date=raw
>         hist = log --pretty=format:\"%h %ad %cd %s%d [%an]\" --graph
> --date=format-local:'%Y-%m-%d %H:%M:%S'
>         hist = log --pretty=format:\"%h %ad %s%d [%an]\" --graph
> --date=format-local:'%Y-%m-%d %H:%M:%S'
>         type = cat-file -t
>         dump = cat-file -p
>         df = diff --color
>         dw = diff --color --word-diff
>         dm = difftool -t meld
>         dy = difftool -t meld -y
> doj at sbc:~$
>
> git clone https://github.com/james-prior/kraftur-math-game.git
> cd kraftur-math-game
> git co jep-dev
> git hist --color=always | grep --color=always '([^)].*)\|$'
> git hist | tac | awk 'NR > 1 {print $2}' | while read h; do git difftool
> -t meld -y "$h"^ "$h" simpleMathGame.py;done
>
> recent notebooks: (not all are posted yet)
>
>     http://nbviewer.jupyter.org/github/james-prior/cohpy/blob/
> master/20170927-dojo-qtconsole-not-happy.ipynb
>     http://nbviewer.jupyter.org/github/james-prior/cohpy/blob/
> master/20170928-dojo-iterating-over-dictionary-gets-keys.ipynb
>     http://nbviewer.jupyter.org/github/james-prior/cohpy/blob/
> master/20170928-dojo-iter-sentinel-else.ipynb
>     http://nbviewer.jupyter.org/github/james-prior/cohpy/blob/
> master/20170928-dojo-refactoring-kraftur-math-game.ipynb
>     http://nbviewer.jupyter.org/github/james-prior/cohpy/blob/
> master/20170928-dojo-references-map-zip_longest-fstrings.ipynb
>
> wp:The Unix Programming Environment
>
> wp: prefix means Wikipedia
> To get good answers, consider following the advice in the links below.
> http://catb.org/~esr/faqs/smart-questions.html
> http://web.archive.org/web/20090627155454/www.greenend.
> org.uk/rjk/2000/06/14/quoting.html
>
> V. Anton Spraul's Think Like a Programmer, Python Edition
> http://www.linuxjournal.com/content/v-anton-sprauls-think-
> programmer-python-edition
>
> Open source-based business lessons from a seasoned CEO
> https://opensource.com/article/17/9/qa-evan-powell
>
> http://thefaradayproject.com/concept/
>
> xdpyinfo | less
>
> Facebook Relents on React.js License Issue
> http://windowsitpro.com/open-source/facebook-relents-reactjs-license-issue
>
> autonomous car uses Python
>
>     Donkey Car
>     http://www.donkeycar.com/
>
>     Joint Meetup with VR Columbus: VR demo and robotics racing in the works
>     https://www.meetup.com/AutonomyHub/events/243521906/
>
> Ohio Linuxfest 2017
> 2017-09-29 to 2017-09-30
>
> Columbus Code Camp
> 2017-10-14
> http://columbuscodecamp.com/
>
> DevOps Days
> https://www.devopsdays.org/events/2017-ohio/
> Wednesday, Nov 8, 2017 - Thursday, Nov 9, 2017
> The Bluestone
>
> Machine Vision with Python
>     openmv (open machine vision)
>     https://openmv.io/
>     https://github.com/openmv/openmv
>     (opencv is too slow)
>
> What are the 7 stages of becoming a Python programmer?
> The 7 stages of becoming a Go programmer
> https://opensource.com/article/17/9/seven-stages-becoming-go-programmer
>
> Microsoft is Doing to ?Open Source? (OSI) What it Did to W3C
> http://techrights.org/2017/09/28/osi-and-microsoft/
>
> https://www.reddit.com/r/dailyprogrammer/comments/
> 6zvjre/20170913_challenge_331_intermediate_sum_of_digits/
> _______________________________________________
> CentralOH mailing list
> CentralOH at python.org
> https://mail.python.org/mailman/listinfo/centraloh
>
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From dallascboys413 at gmail.com  Thu Oct  5 07:23:06 2017
From: dallascboys413 at gmail.com (Jacob Escobedo)
Date: Thu, 5 Oct 2017 07:23:06 -0400
Subject: [CentralOH] Beginner python user
In-Reply-To: <CAAOWqTVhdebU-0=4feFNU=sUOkDi70svKsRAimhiFEqQR-BJXg@mail.gmail.com>
References: <CAAOWqTVq2AO+w6xxuksfT9NYCgfCK=Rhh8JNs2JURyE9NfbuCQ@mail.gmail.com>
 <CAAOWqTUKP-S3CU4CyoJAo44THv2dCpVAu02for1LXccFhdB=Wg@mail.gmail.com>
 <CAAOWqTVzzXfr0UawPPRmHPOXS-E8ZU=iQmUGHme4TfzRNmUVCQ@mail.gmail.com>
 <CAAOWqTVX6fCSuby9z9bDTvxw5Ue8nbv4FTTm=SQtrEDnOtDJvA@mail.gmail.com>
 <CAAOWqTWLEkZF_xc5fNCSbFVOvhnB--WJWrDAqDcSFWH=wFB1hA@mail.gmail.com>
 <CAAOWqTWzQ63oz_sXEPvX5uNSXm7oVsX8FEb9aJf5o4ZKXZd2Pg@mail.gmail.com>
 <CAAOWqTUCVQpPVSGwXhjrRY-9gLZKMsFvUsWnDeC0Tyv-aXSimA@mail.gmail.com>
 <CAAOWqTXq=61pawPpkbzwdCxTyWa+O+_dJRQK5bJ6ktvEWPQq0A@mail.gmail.com>
 <CAAOWqTVhdebU-0=4feFNU=sUOkDi70svKsRAimhiFEqQR-BJXg@mail.gmail.com>
Message-ID: <CAAOWqTXgbdAEvC5_iNciw=sv5D42_43WMsNdbUf8Ug3Q6b_unw@mail.gmail.com>

Hello everyone,

I have just started to dip my toes into python and I am looking for mentors
and peers to help me learn.

I am doing some free course and other material I have found online. My goal
is to self teach using all these free courses and resources I have found.

I would love to meet some people not only during the meetups but outside of
it so I can pick your brain asking questions and other things to help me
along my way.

If you want to be a mentor or any advice that would be awesome.

Thank you,

Jacob
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From y2k at y2kbugger.com  Thu Oct  5 10:06:39 2017
From: y2k at y2kbugger.com (Zak Kohler)
Date: Thu, 5 Oct 2017 10:06:39 -0400
Subject: [CentralOH] Beginner python user
In-Reply-To: <CAAOWqTXgbdAEvC5_iNciw=sv5D42_43WMsNdbUf8Ug3Q6b_unw@mail.gmail.com>
References: <CAAOWqTVq2AO+w6xxuksfT9NYCgfCK=Rhh8JNs2JURyE9NfbuCQ@mail.gmail.com>
 <CAAOWqTUKP-S3CU4CyoJAo44THv2dCpVAu02for1LXccFhdB=Wg@mail.gmail.com>
 <CAAOWqTVzzXfr0UawPPRmHPOXS-E8ZU=iQmUGHme4TfzRNmUVCQ@mail.gmail.com>
 <CAAOWqTVX6fCSuby9z9bDTvxw5Ue8nbv4FTTm=SQtrEDnOtDJvA@mail.gmail.com>
 <CAAOWqTWLEkZF_xc5fNCSbFVOvhnB--WJWrDAqDcSFWH=wFB1hA@mail.gmail.com>
 <CAAOWqTWzQ63oz_sXEPvX5uNSXm7oVsX8FEb9aJf5o4ZKXZd2Pg@mail.gmail.com>
 <CAAOWqTUCVQpPVSGwXhjrRY-9gLZKMsFvUsWnDeC0Tyv-aXSimA@mail.gmail.com>
 <CAAOWqTXq=61pawPpkbzwdCxTyWa+O+_dJRQK5bJ6ktvEWPQq0A@mail.gmail.com>
 <CAAOWqTVhdebU-0=4feFNU=sUOkDi70svKsRAimhiFEqQR-BJXg@mail.gmail.com>
 <CAAOWqTXgbdAEvC5_iNciw=sv5D42_43WMsNdbUf8Ug3Q6b_unw@mail.gmail.com>
Message-ID: <CAD8FQQ0TCD7RatKDohJ_4pi7HE5+zzSi9GsS67x3urLemaf4jQ@mail.gmail.com>

Where are you located?

On Thu, Oct 5, 2017 at 7:23 AM, Jacob Escobedo <dallascboys413 at gmail.com>
wrote:

> Hello everyone,
>
> I have just started to dip my toes into python and I am looking for
> mentors and peers to help me learn.
>
> I am doing some free course and other material I have found online. My
> goal is to self teach using all these free courses and resources I have
> found.
>
> I would love to meet some people not only during the meetups but outside
> of it so I can pick your brain asking questions and other things to help me
> along my way.
>
> If you want to be a mentor or any advice that would be awesome.
>
> Thank you,
>
> Jacob
>
> _______________________________________________
> CentralOH mailing list
> CentralOH at python.org
> https://mail.python.org/mailman/listinfo/centraloh
>
>
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From dallascboys413 at gmail.com  Thu Oct  5 10:31:28 2017
From: dallascboys413 at gmail.com (Jacob Escobedo)
Date: Thu, 5 Oct 2017 10:31:28 -0400
Subject: [CentralOH] Beginner python user
In-Reply-To: <CAD8FQQ0TCD7RatKDohJ_4pi7HE5+zzSi9GsS67x3urLemaf4jQ@mail.gmail.com>
References: <CAAOWqTVq2AO+w6xxuksfT9NYCgfCK=Rhh8JNs2JURyE9NfbuCQ@mail.gmail.com>
 <CAAOWqTUKP-S3CU4CyoJAo44THv2dCpVAu02for1LXccFhdB=Wg@mail.gmail.com>
 <CAAOWqTVzzXfr0UawPPRmHPOXS-E8ZU=iQmUGHme4TfzRNmUVCQ@mail.gmail.com>
 <CAAOWqTVX6fCSuby9z9bDTvxw5Ue8nbv4FTTm=SQtrEDnOtDJvA@mail.gmail.com>
 <CAAOWqTWLEkZF_xc5fNCSbFVOvhnB--WJWrDAqDcSFWH=wFB1hA@mail.gmail.com>
 <CAAOWqTWzQ63oz_sXEPvX5uNSXm7oVsX8FEb9aJf5o4ZKXZd2Pg@mail.gmail.com>
 <CAAOWqTUCVQpPVSGwXhjrRY-9gLZKMsFvUsWnDeC0Tyv-aXSimA@mail.gmail.com>
 <CAAOWqTXq=61pawPpkbzwdCxTyWa+O+_dJRQK5bJ6ktvEWPQq0A@mail.gmail.com>
 <CAAOWqTVhdebU-0=4feFNU=sUOkDi70svKsRAimhiFEqQR-BJXg@mail.gmail.com>
 <CAAOWqTXgbdAEvC5_iNciw=sv5D42_43WMsNdbUf8Ug3Q6b_unw@mail.gmail.com>
 <CAD8FQQ0TCD7RatKDohJ_4pi7HE5+zzSi9GsS67x3urLemaf4jQ@mail.gmail.com>
Message-ID: <CAAOWqTWOLgsv87xN3Y02s0syaa76+5F4r2PYcDUHTeUUkx15kA@mail.gmail.com>

Dublin area, off sawmill

On Oct 5, 2017 10:19 AM, "Zak Kohler" <y2k at y2kbugger.com> wrote:

> Where are you located?
>
> On Thu, Oct 5, 2017 at 7:23 AM, Jacob Escobedo <dallascboys413 at gmail.com>
> wrote:
>
>> Hello everyone,
>>
>> I have just started to dip my toes into python and I am looking for
>> mentors and peers to help me learn.
>>
>> I am doing some free course and other material I have found online. My
>> goal is to self teach using all these free courses and resources I have
>> found.
>>
>> I would love to meet some people not only during the meetups but outside
>> of it so I can pick your brain asking questions and other things to help me
>> along my way.
>>
>> If you want to be a mentor or any advice that would be awesome.
>>
>> Thank you,
>>
>> Jacob
>>
>> _______________________________________________
>> CentralOH mailing list
>> CentralOH at python.org
>> https://mail.python.org/mailman/listinfo/centraloh
>>
>>
>
> _______________________________________________
> CentralOH mailing list
> CentralOH at python.org
> https://mail.python.org/mailman/listinfo/centraloh
>
>
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From pybokeh at gmail.com  Thu Oct  5 10:44:49 2017
From: pybokeh at gmail.com (pybokeh)
Date: Thu, 5 Oct 2017 10:44:49 -0400
Subject: [CentralOH] Beginner python user
In-Reply-To: <CAAOWqTXgbdAEvC5_iNciw=sv5D42_43WMsNdbUf8Ug3Q6b_unw@mail.gmail.com>
References: <CAAOWqTVq2AO+w6xxuksfT9NYCgfCK=Rhh8JNs2JURyE9NfbuCQ@mail.gmail.com>
 <CAAOWqTUKP-S3CU4CyoJAo44THv2dCpVAu02for1LXccFhdB=Wg@mail.gmail.com>
 <CAAOWqTVzzXfr0UawPPRmHPOXS-E8ZU=iQmUGHme4TfzRNmUVCQ@mail.gmail.com>
 <CAAOWqTVX6fCSuby9z9bDTvxw5Ue8nbv4FTTm=SQtrEDnOtDJvA@mail.gmail.com>
 <CAAOWqTWLEkZF_xc5fNCSbFVOvhnB--WJWrDAqDcSFWH=wFB1hA@mail.gmail.com>
 <CAAOWqTWzQ63oz_sXEPvX5uNSXm7oVsX8FEb9aJf5o4ZKXZd2Pg@mail.gmail.com>
 <CAAOWqTUCVQpPVSGwXhjrRY-9gLZKMsFvUsWnDeC0Tyv-aXSimA@mail.gmail.com>
 <CAAOWqTXq=61pawPpkbzwdCxTyWa+O+_dJRQK5bJ6ktvEWPQq0A@mail.gmail.com>
 <CAAOWqTVhdebU-0=4feFNU=sUOkDi70svKsRAimhiFEqQR-BJXg@mail.gmail.com>
 <CAAOWqTXgbdAEvC5_iNciw=sv5D42_43WMsNdbUf8Ug3Q6b_unw@mail.gmail.com>
Message-ID: <CAOoMBVjRW=K7Agmw4WFS2Jr9ewrp_DsyYz5A4VsH708LFzbXCQ@mail.gmail.com>

I'm in Dublin also.  I can help when I can.  But, if you're primarily
interested in web development, I would suggest getting help from others.  I
only have basic knowledge in web dev.  My domain knowledge is in data
analysis or data science.  It would help if you tell us what you want to
use Python for.  I understand if you don't know at this moment, but would
help in narrowing the focus.  Python can be used for a lot of things.

- Daniel
pybokeh at gmail.com


On Oct 5, 2017 9:39 AM, "Jacob Escobedo" <dallascboys413 at gmail.com> wrote:

Hello everyone,

I have just started to dip my toes into python and I am looking for mentors
and peers to help me learn.

I am doing some free course and other material I have found online. My goal
is to self teach using all these free courses and resources I have found.

I would love to meet some people not only during the meetups but outside of
it so I can pick your brain asking questions and other things to help me
along my way.

If you want to be a mentor or any advice that would be awesome.

Thank you,

Jacob

_______________________________________________
CentralOH mailing list
CentralOH at python.org
https://mail.python.org/mailman/listinfo/centraloh
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From dallascboys413 at gmail.com  Thu Oct  5 11:33:33 2017
From: dallascboys413 at gmail.com (Jacob Escobedo)
Date: Thu, 5 Oct 2017 11:33:33 -0400
Subject: [CentralOH] Beginner python user
In-Reply-To: <CAOoMBVjRW=K7Agmw4WFS2Jr9ewrp_DsyYz5A4VsH708LFzbXCQ@mail.gmail.com>
References: <CAAOWqTVq2AO+w6xxuksfT9NYCgfCK=Rhh8JNs2JURyE9NfbuCQ@mail.gmail.com>
 <CAAOWqTUKP-S3CU4CyoJAo44THv2dCpVAu02for1LXccFhdB=Wg@mail.gmail.com>
 <CAAOWqTVzzXfr0UawPPRmHPOXS-E8ZU=iQmUGHme4TfzRNmUVCQ@mail.gmail.com>
 <CAAOWqTVX6fCSuby9z9bDTvxw5Ue8nbv4FTTm=SQtrEDnOtDJvA@mail.gmail.com>
 <CAAOWqTWLEkZF_xc5fNCSbFVOvhnB--WJWrDAqDcSFWH=wFB1hA@mail.gmail.com>
 <CAAOWqTWzQ63oz_sXEPvX5uNSXm7oVsX8FEb9aJf5o4ZKXZd2Pg@mail.gmail.com>
 <CAAOWqTUCVQpPVSGwXhjrRY-9gLZKMsFvUsWnDeC0Tyv-aXSimA@mail.gmail.com>
 <CAAOWqTXq=61pawPpkbzwdCxTyWa+O+_dJRQK5bJ6ktvEWPQq0A@mail.gmail.com>
 <CAAOWqTVhdebU-0=4feFNU=sUOkDi70svKsRAimhiFEqQR-BJXg@mail.gmail.com>
 <CAAOWqTXgbdAEvC5_iNciw=sv5D42_43WMsNdbUf8Ug3Q6b_unw@mail.gmail.com>
 <CAOoMBVjRW=K7Agmw4WFS2Jr9ewrp_DsyYz5A4VsH708LFzbXCQ@mail.gmail.com>
Message-ID: <CAAOWqTU16LeM7KMAHuU=jSRCK9SX+SS6rw6ev55ANS=Af3HPLA@mail.gmail.com>

Yeah I'm leaning towards web development, but since I am new I'm not only
focusing on that because I don't know what I enjoy doing yet.


Jacob

On Oct 5, 2017 10:45 AM, "pybokeh" <pybokeh at gmail.com> wrote:

> I'm in Dublin also.  I can help when I can.  But, if you're primarily
> interested in web development, I would suggest getting help from others.  I
> only have basic knowledge in web dev.  My domain knowledge is in data
> analysis or data science.  It would help if you tell us what you want to
> use Python for.  I understand if you don't know at this moment, but would
> help in narrowing the focus.  Python can be used for a lot of things.
>
> - Daniel
> pybokeh at gmail.com
>
>
> On Oct 5, 2017 9:39 AM, "Jacob Escobedo" <dallascboys413 at gmail.com> wrote:
>
> Hello everyone,
>
> I have just started to dip my toes into python and I am looking for
> mentors and peers to help me learn.
>
> I am doing some free course and other material I have found online. My
> goal is to self teach using all these free courses and resources I have
> found.
>
> I would love to meet some people not only during the meetups but outside
> of it so I can pick your brain asking questions and other things to help me
> along my way.
>
> If you want to be a mentor or any advice that would be awesome.
>
> Thank you,
>
> Jacob
>
> _______________________________________________
> CentralOH mailing list
> CentralOH at python.org
> https://mail.python.org/mailman/listinfo/centraloh
>
>
>
> _______________________________________________
> CentralOH mailing list
> CentralOH at python.org
> https://mail.python.org/mailman/listinfo/centraloh
>
>
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From jep200404 at columbus.rr.com  Thu Oct  5 12:44:51 2017
From: jep200404 at columbus.rr.com (jep200404 at columbus.rr.com)
Date: Thu, 5 Oct 2017 12:44:51 -0400
Subject: [CentralOH] Beginner python user
In-Reply-To: <CAAOWqTXgbdAEvC5_iNciw=sv5D42_43WMsNdbUf8Ug3Q6b_unw@mail.gmail.com>
References: <CAAOWqTVq2AO+w6xxuksfT9NYCgfCK=Rhh8JNs2JURyE9NfbuCQ@mail.gmail.com>
 <CAAOWqTUKP-S3CU4CyoJAo44THv2dCpVAu02for1LXccFhdB=Wg@mail.gmail.com>
 <CAAOWqTVzzXfr0UawPPRmHPOXS-E8ZU=iQmUGHme4TfzRNmUVCQ@mail.gmail.com>
 <CAAOWqTVX6fCSuby9z9bDTvxw5Ue8nbv4FTTm=SQtrEDnOtDJvA@mail.gmail.com>
 <CAAOWqTWLEkZF_xc5fNCSbFVOvhnB--WJWrDAqDcSFWH=wFB1hA@mail.gmail.com>
 <CAAOWqTWzQ63oz_sXEPvX5uNSXm7oVsX8FEb9aJf5o4ZKXZd2Pg@mail.gmail.com>
 <CAAOWqTUCVQpPVSGwXhjrRY-9gLZKMsFvUsWnDeC0Tyv-aXSimA@mail.gmail.com>
 <CAAOWqTXq=61pawPpkbzwdCxTyWa+O+_dJRQK5bJ6ktvEWPQq0A@mail.gmail.com>
 <CAAOWqTVhdebU-0=4feFNU=sUOkDi70svKsRAimhiFEqQR-BJXg@mail.gmail.com>
 <CAAOWqTXgbdAEvC5_iNciw=sv5D42_43WMsNdbUf8Ug3Q6b_unw@mail.gmail.com>
Message-ID: <20171005124451.3d038f17.jep200404@columbus.rr.com>

On Thu, 5 Oct 2017 07:23:06 -0400, Jacob Escobedo <dallascboys413 at gmail.com> wrote:

> I would love to meet some people not only during the meetups but outside of
> it so I can pick your brain asking questions and other things to help me
> along my way.

The weekly dojos are the place for exactly that.
There is one tonight. See cohpy.org.

From dallascboys413 at gmail.com  Thu Oct  5 16:51:42 2017
From: dallascboys413 at gmail.com (Jacob Escobedo)
Date: Thu, 5 Oct 2017 16:51:42 -0400
Subject: [CentralOH] Beginner python user
In-Reply-To: <20171005124451.3d038f17.jep200404@columbus.rr.com>
References: <CAAOWqTVq2AO+w6xxuksfT9NYCgfCK=Rhh8JNs2JURyE9NfbuCQ@mail.gmail.com>
 <CAAOWqTUKP-S3CU4CyoJAo44THv2dCpVAu02for1LXccFhdB=Wg@mail.gmail.com>
 <CAAOWqTVzzXfr0UawPPRmHPOXS-E8ZU=iQmUGHme4TfzRNmUVCQ@mail.gmail.com>
 <CAAOWqTVX6fCSuby9z9bDTvxw5Ue8nbv4FTTm=SQtrEDnOtDJvA@mail.gmail.com>
 <CAAOWqTWLEkZF_xc5fNCSbFVOvhnB--WJWrDAqDcSFWH=wFB1hA@mail.gmail.com>
 <CAAOWqTWzQ63oz_sXEPvX5uNSXm7oVsX8FEb9aJf5o4ZKXZd2Pg@mail.gmail.com>
 <CAAOWqTUCVQpPVSGwXhjrRY-9gLZKMsFvUsWnDeC0Tyv-aXSimA@mail.gmail.com>
 <CAAOWqTXq=61pawPpkbzwdCxTyWa+O+_dJRQK5bJ6ktvEWPQq0A@mail.gmail.com>
 <CAAOWqTVhdebU-0=4feFNU=sUOkDi70svKsRAimhiFEqQR-BJXg@mail.gmail.com>
 <CAAOWqTXgbdAEvC5_iNciw=sv5D42_43WMsNdbUf8Ug3Q6b_unw@mail.gmail.com>
 <20171005124451.3d038f17.jep200404@columbus.rr.com>
Message-ID: <CAAOWqTVcEAovRuXWM4whGKWe9R_miRFF1or1sMJKwZaE8Lhk9A@mail.gmail.com>

Ok awesome I'll try to make it to all of those, unfortunately I can't
tonight.

Jacob

On Oct 5, 2017 12:45 PM, <jep200404 at columbus.rr.com> wrote:

> On Thu, 5 Oct 2017 07:23:06 -0400, Jacob Escobedo <
> dallascboys413 at gmail.com> wrote:
>
> > I would love to meet some people not only during the meetups but outside
> of
> > it so I can pick your brain asking questions and other things to help me
> > along my way.
>
> The weekly dojos are the place for exactly that.
> There is one tonight. See cohpy.org.
> _______________________________________________
> CentralOH mailing list
> CentralOH at python.org
> https://mail.python.org/mailman/listinfo/centraloh
>
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From jep200404 at columbus.rr.com  Fri Oct  6 01:47:52 2017
From: jep200404 at columbus.rr.com (jep200404 at columbus.rr.com)
Date: Fri, 6 Oct 2017 01:47:52 -0400
Subject: [CentralOH] =?utf-8?q?2017-10-05_=E9=81=93=E5=A0=B4_Scribbles_?=
 =?utf-8?b?76SY5pu4L+aDoeaWhz8gaXRlcihmdW5jdGlvbiwgc2VudGluZWwpOyA4MCBj?=
 =?utf-8?q?haracters_per_line?=
Message-ID: <20171006014752.6a2563bf.jep200404@columbus.rr.com>

crowded tonight

iter() with two arguments is good to know

    Compare cells 4 and 6 of:
    http://nbviewer.jupyter.org/github/james-prior/cohpy/blob/master/20160708-dojo-user-input-loop-with-iter-partial-input-prompt-sentinel.ipynb

    http://nbviewer.jupyter.org/github/james-prior/cohpy/blob/master/20160603-dojo-iter-second-argument.ipynb
    http://nbviewer.jupyter.org/github/james-prior/cohpy/blob/master/20170928-dojo-iter-sentinel-else.ipynb

max 80 characters per line

    to make it easy for people to read

        it's hard for people to read long lines
        my monitor can show 425 characters per line,
        my eyes can see it just fine
        but my brain has a tough time comprehending long lines

    newspapers chop width of paper up into narrow columns
    so that they are easy to read

    PEP 8
    https://www.python.org/dev/peps/pep-0008/#maximum-line-length

        Limit all lines to a maximum of 79 characters.

    Linux kernel coding style:
    https://www.kernel.org/doc/html/latest/process/coding-style.html#breaking-long-lines-and-strings

        The limit on the length of lines is 80 columns and this is a
        strongly preferred limit

    Quoting Style
    http://web.archive.org/web/20090627155454/www.greenend.org.uk/rjk/2000/06/14/quoting.html

        Broadly speaking, USENET articles should fit into 80 columns. A
        common recommendation is to keep new text wrapped at 72 columns,
        so that there is space for it to be quoted several times without
        exceeding the 80 column limit.

    How To Ask Questions The Smart Way
    http://catb.org/~esr/faqs/smart-questions.html

        Don't send e-mail in which entire paragraphs are single
        multiply-wrapped lines. (This makes it too difficult to reply to
        just part of the message.) Assume that your respondents will be
        reading mail on 80-character-wide text displays and set your
        line wrap accordingly, to something less than 80.

    what is url for zed shaw's recommendation?

3 Python web scrapers and crawlers
https://opensource.com/resources/python/web-scraper-crawler

100 day coding challenge
https://github.com/Kallaway/100-days-of-code

Giant python attacks Indonesian man before being eaten
http://www.pulse.ng/news/world/in-indonesia-giant-python-attacks-man-before-being-eaten-id7414025.html
http://www.breitbart.com/news/giant-python-attacks-indonesian-man-before-being-eaten/

Adopting minimalism in your docs
https://opensource.com/article/17/9/adopting-minimalism-your-docs

Subutai: AirBnB for cloud computing
http://www.linuxjournal.com/content/say-hi-subutai
wp:Subutai

wp: prefix means Wikipedia
To get good answers, consider following the advice in the links below.
http://catb.org/~esr/faqs/smart-questions.html
http://web.archive.org/web/20090627155454/www.greenend.org.uk/rjk/2000/06/14/quoting.html

From jep200404 at columbus.rr.com  Sun Oct  8 17:18:09 2017
From: jep200404 at columbus.rr.com (jep200404 at columbus.rr.com)
Date: Sun, 8 Oct 2017 17:18:09 -0400
Subject: [CentralOH] 2017-10-19 11:30 Python Lunch at The Crest Gastropub
Message-ID: <20171008171809.5ccc29ae.jep200404@columbus.rr.com>

Python Lunch at The Crest Gastropub[1]
October 19, 2017, 11:30 a.m.

We'll be meeting at The Crest Gastropub, 2855 Indianola Ave.,
for good food and good company.
Join us to talk Python, programming, or anything else!

[1] The Crest Gastropub, 2855 Indianola Ave, Columbus, OH 43202[1]
    http://www.openstreetmap.org/way/389102227#map=16/40.0218/-83.0023


From miller.eric.t at gmail.com  Mon Oct  9 10:53:41 2017
From: miller.eric.t at gmail.com (Eric Miller)
Date: Mon, 9 Oct 2017 10:53:41 -0400
Subject: [CentralOH] PyCon 2018 CFP is Open!
In-Reply-To: <CAKMnukqUhE3PE7yhKp7u=nok=CnWScTo0HcVuqUa1+bSS4P4XA@mail.gmail.com>
References: <CAKMnukqUhE3PE7yhKp7u=nok=CnWScTo0HcVuqUa1+bSS4P4XA@mail.gmail.com>
Message-ID: <CAN67YM66g7X9e7xybCQ-BB-1M-j5D_-gr69d2gMQJX9L5VdAvw@mail.gmail.com>

Hey Betsy-

Are there any specific subject matter areas that the organizers are
targeting for pc2018?  e.g. 'we really hope to have entries for <some
subject(s)>' ?

On Thu, Sep 28, 2017 at 5:06 PM, Betsy Waliszewski <betsy at python.org> wrote:

> Hi,
>
> Woohoo! The PyCon 2018 CFP is open!
>
> Here is a link to all the information: https://us.pycon.org/2018/speaking/
>
>    - Tutorial proposals ? deadline is 24 November 2017 AoE.
>    - Talk, Poster, and Education Summit proposals ? deadline is 3 January
>    2018 AoE.
>
> If you know of a company who might be interested in sponsoring, feel free
> to share our prospectus: https://us.pycon.org/2018/sponsors/prospectus/.
> An email intro to me would be wonderful.
>
> Cheers,
>
> Betsy
>
> _______________________________________________
> CentralOH mailing list
> CentralOH at python.org
> https://mail.python.org/mailman/listinfo/centraloh
>
>
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From eric at intellovations.com  Mon Oct  9 16:29:41 2017
From: eric at intellovations.com (Eric Floehr)
Date: Mon, 9 Oct 2017 16:29:41 -0400
Subject: [CentralOH] 2017-10-19 11:30 Python Lunch at The Crest Gastropub
In-Reply-To: <20171008171809.5ccc29ae.jep200404@columbus.rr.com>
References: <20171008171809.5ccc29ae.jep200404@columbus.rr.com>
Message-ID: <CAJzarMO_RiTx=2iqUd6Fh_XHCAUCSDM3Ucsh8uc4_sCNAvTyFQ@mail.gmail.com>

RSVP Here:
https://www.meetup.com/Central-Ohio-Python-Users-Group/events/244064324/



On Sun, Oct 8, 2017 at 5:18 PM, <jep200404 at columbus.rr.com> wrote:

> Python Lunch at The Crest Gastropub[1]
> October 19, 2017, 11:30 a.m.
>
> We'll be meeting at The Crest Gastropub, 2855 Indianola Ave.,
> for good food and good company.
> Join us to talk Python, programming, or anything else!
>
> [1] The Crest Gastropub, 2855 Indianola Ave, Columbus, OH 43202[1]
>     http://www.openstreetmap.org/way/389102227#map=16/40.0218/-83.0023
>
> _______________________________________________
> CentralOH mailing list
> CentralOH at python.org
> https://mail.python.org/mailman/listinfo/centraloh
>
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From brian.costlow at gmail.com  Mon Oct  9 20:45:45 2017
From: brian.costlow at gmail.com (Brian Costlow)
Date: Mon, 9 Oct 2017 20:45:45 -0400
Subject: [CentralOH] Short term python gig available.
Message-ID: <CACLJ_dGq3uJPbWyUG1JZiMDFX3RRbRmB9nPGvKHzU0EbjQbjvQ@mail.gmail.com>

I have a line on a Python project that would probably run until years end.

Combination of custom Python code and Jenkins work for a CI/CD system.

Contact me if interested.
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From brian.costlow at gmail.com  Wed Oct 11 19:08:49 2017
From: brian.costlow at gmail.com (Brian Costlow)
Date: Wed, 11 Oct 2017 19:08:49 -0400
Subject: [CentralOH] 4th Annual Columbus Tech Community Holiday Party
Message-ID: <CACLJ_dFU3cnqT7GBfEZR1NJt5FqKJRgRHQKzuxFFPQJ8DbV8NA@mail.gmail.com>

Hope to see everyone there!

http://columbusholidayparty.com/
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From jep200404 at columbus.rr.com  Thu Oct 12 23:30:38 2017
From: jep200404 at columbus.rr.com (jep200404 at columbus.rr.com)
Date: Thu, 12 Oct 2017 23:30:38 -0400
Subject: [CentralOH] =?utf-8?q?2017-10-12_=E9=81=93=E5=A0=B4_Scribbles_?=
 =?utf-8?b?76SY5pu4L+aDoeaWhz8gLnNwbGl0IC5qb2luIGFjY3VtdWxhdGUgZ2VuZXJh?=
 =?utf-8?q?tors_even_fibonacci_numbers_recursion?=
Message-ID: <20171012233038.4b475d8e.jep200404@columbus.rr.com>

    git hist | tac | awk 'NR > 1 {print $2}' | while read h; do git dy "$h"^ "$h" simpleMathGame.py;done

    nested calls that never return

many folks again tonight

some code from tonight:

    http://nbviewer.jupyter.org/github/james-prior/cohpy/blob/master/20171012-dojo-splitting-and-joining-for-anki.ipynb
    http://nbviewer.jupyter.org/github/james-prior/cohpy/blob/master/20171012-dojo-generators.ipynb
    http://nbviewer.jupyter.org/github/james-prior/cohpy/blob/master/20171012-dojo-getting-attributes-of-object-by-name.ipynb

Hopefully the person working on the anki stuff will post the many versions of
main() that read and wrote a tab delimited file.

Python's csv module is wunnerfull
https://docs.python.org/3/library/csv.html#csv.DictReader

wp:Project Euler
https://projecteuler.net/archives

    problem #2: sum of even fibonacci numbers

        wp:Fibonacci number
        calculate fibonacci numbers recursively

            http://nbviewer.jupyter.org/github/james-prior/cohpy/blob/master/20150223-cohpy-memoization.ipynb

        http://nbviewer.jupyter.org/github/james-prior/euler/blob/master/euler-002-even-fibonacci-numbers-20130607.ipynb
        http://nbviewer.jupyter.org/github/james-prior/euler/blob/master/euler-002-even-fibonacci-numbers-20130729.ipynb
        http://nbviewer.jupyter.org/github/cohpy/challenge-201605-generators/blob/master/james-prior/8-nested-generators-20160626-1920.ipynb

wp:Shibboleth

wp: prefix means Wikipedia
To get good answers, consider following the advice in the links below.
http://catb.org/~esr/faqs/smart-questions.html
http://web.archive.org/web/20090627155454/www.greenend.org.uk/rjk/2000/06/14/quoting.html

git push -f -u origin master

pyperclip
http://pypi.python.org/pypi/pyperclip

find | grep foo
find -name '*.py' | grep -v '^[.]/env/' | xargs grep -H whatever

wp:Stroop effect

Purism Linux smartphone makes its $1.5 million crowdfunding goal
http://www.zdnet.com/article/purism-linux-smartphone-makes-its-1-5-million-crowdfunding-goal/

python-hwinfo : Display Summary Of Hardware Information Using Standard Linux Utilities
https://www.2daygeek.com/python-hwinfo-check-display-system-hardware-configuration-information-linux/

Connect To Wifi From The Linux Command Line
https://linuxconfig.org/connect-to-wifi-from-the-linux-command-line

25 Free Books To Learn Linux For Free
https://itsfoss.com/learn-linux-for-free/

compare to jupyter notebook with numpy,scipy,sympy,pandas
Using Octave on Fedora 26
https://fedoramagazine.org/using-octave-fedora-26/

Mozilla pilots Cliqz engine in Firefox to slurp user browsing data
Updated: Mozilla insists the pilot program will improve user privacy, not lessen it.
http://www.zdnet.com/article/firefox-tests-cliqz-engine-which-slurps-user-browsing-data/

Does the last MP3 patent expire on 2017-12-30?
wp:MP3#Licensing.2C_ownership_and_legislation

(Using a python program to:)
Working with YouTube and Extracting Audio
http://www.linuxjournal.com/content/working-youtube-and-extracting-audio
How would you replace the shell scripting with Python?

From jep200404 at columbus.rr.com  Fri Oct 20 22:24:22 2017
From: jep200404 at columbus.rr.com (jep200404 at columbus.rr.com)
Date: Fri, 20 Oct 2017 22:24:22 -0400
Subject: [CentralOH] =?utf-8?b?MjAxNy0xMC0yMCDnh5XmnIggTHVuY2ggUGxhY2Vt?=
 =?utf-8?q?at_Scribbles=3A_tcl_braces_versus_python=3B_fibonacci_versus_ha?=
 =?utf-8?q?mming?=
Message-ID: <20171020222422.124f124b.jep200404@columbus.rr.com>

more code than usual

lunch:

    tcl braces
    versus python
    fibonacci and hamming numbers

tcl without braces is painfully slow

    doj at sbc:~/20171026$ cat FibForXNoBraces.tcl
    proc Fib {n} {

       if {$n == 0} {
          set Ret_Value 0
       } else {
          if {$n < 3} {
             set Ret_Value 1
          } else {
             set PrevVal 1
             set ThisVal 1
             for {set y 3} {$y <= $n} {incr y} {
                set Ret_Value [expr $PrevVal + $ThisVal]
                set PrevVal $ThisVal
                set ThisVal $Ret_Value
             }
          }
       }

       return $Ret_Value

    }

    puts "Please enter seed value:"

    gets stdin x

    set StartTime [clock microseconds]
    set Answer [Fib $x]
    set EndTime [clock microseconds]
    puts "Seed $x; Result $Answer"
    puts "Duration [expr $EndTime - $StartTime] microseconds"
    doj at sbc:~/20171026$ echo 11111 | tclsh FibForXNoBraces.tcl
    Please enter seed value:
    Seed 11111; Result 515...489
    Duration 129277783 microseconds
    doj at sbc:~/20171026$ 

tcl with braces is fast

    doj at sbc:~/20171026$ cat FibForXWithBraces.tcl
    proc Fib {n} {

       if {$n == 0} {
          set Ret_Value 0
       } else {
          if {$n < 3} {
             set Ret_Value 1
          } else {
             set PrevVal 1
             set ThisVal 1
             for {set y 3} {$y <= $n} {incr y} {
                set Ret_Value [expr {$PrevVal + $ThisVal}]
                set PrevVal $ThisVal
                set ThisVal $Ret_Value
             }
          }
       }

       return $Ret_Value
    }

    puts "Please enter seed value:"

    gets stdin x

    set StartTime [clock microseconds]
    set Answer [Fib $x]
    set EndTime [clock microseconds]
    puts "Seed $x; Result $Answer"
    puts "Duration [expr $EndTime - $StartTime] microseconds"
    doj at sbc:~/20171026$ diff FibForXNoBraces.tcl FibForXWithBraces.tcl
    12c12
    <             set Ret_Value [expr $PrevVal + $ThisVal]
    ---
    >             set Ret_Value [expr {$PrevVal + $ThisVal}]
    doj at sbc:~/20171026$ echo 11111 | tclsh FibForXWithBraces.tcl 
    Please enter seed value:
    Seed 11111; Result 515...489
    Duration 42093 microseconds
    doj at sbc:~/20171026$ 

regular Python is faster

    (jupy) doj at sbc:~/20171026$ cat fib.py 
    #!/usr/bin/env python3

    import sys
    from timeit import timeit

    source_code = '''
    def fib(n):
        if n == 0:
            return 0
        a, b = 0, 1
        for _ in range(n):
            a, b = b, a + b
        return a
    '''

    exec(source_code)

    def main():
        for arg in sys.argv[1:]:
            n = int(arg)
            number = 1000
            elapsed_time = timeit('fib(%s)' % n, setup=source_code, number=number)
            print(
                f'{elapsed_time}s total / {number} loops -> '
                f'{elapsed_time / number}s per loop for fib({n}) -> {fib(n)}'
            )

    if __name__ == '__main__':
        main()
    (jupy) doj at sbc:~/20171026$ ./fib.py 0 1 2 3 4 5 6 7 11111
    0.00038148299790918827s total / 1000 loops -> 3.814829979091883e-07s per loop for fib(0) -> 0
    0.0018241599900647998s total / 1000 loops -> 1.8241599900647999e-06s per loop for fib(1) -> 1
    0.0020077070221304893s total / 1000 loops -> 2.0077070221304894e-06s per loop for fib(2) -> 1
    0.002059810038190335s total / 1000 loops -> 2.059810038190335e-06s per loop for fib(3) -> 2
    0.0022625650162808597s total / 1000 loops -> 2.26256501628086e-06s per loop for fib(4) -> 3
    0.0025070849806070328s total / 1000 loops -> 2.5070849806070328e-06s per loop for fib(5) -> 5
    0.0026626960025168955s total / 1000 loops -> 2.6626960025168955e-06s per loop for fib(6) -> 8
    0.002945350017398596s total / 1000 loops -> 2.945350017398596e-06s per loop for fib(7) -> 13
    8.536355245974846s total / 1000 loops -> 0.008536355245974845s per loop for fib(11111) -> 515...489
    (jupy) doj at sbc:~/20171026$ 

pypy is faster yet.
This is the first time that I have used pypy.

    (jupy) doj at sbc:~/20171026$ cat fibpypy.py
    #!/usr/bin/env pypy

    import sys
    from timeit import timeit

    source_code = '''
    def fib(n):
        if n == 0:
            return 0
        a, b = 0, 1
        for _ in range(n):
            a, b = b, a + b
        return a
    '''

    exec(source_code)

    def main():
        for arg in sys.argv[1:]:
            n = int(arg)
            number = 1000
            elapsed_time = timeit('fib(%s)' % n, setup=source_code, number=number)
            print(
                '{0}s total / {1} loops -> '
                '{2}s per loop for fib({3}) -> {4}'.format(
                    elapsed_time,
                    number,
                    elapsed_time / number,
                    n,
                    fib(n),
                )
            )

    if __name__ == '__main__':
        main()
    (jupy) doj at sbc:~/20171026$ diff fib.py fibpypy.py 
    1c1
    < #!/usr/bin/env python3
    ---
    > #!/usr/bin/env pypy
    24,25c24,31
    <             f'{elapsed_time}s total / {number} loops -> '
    <             f'{elapsed_time / number}s per loop for fib({n}) -> {fib(n)}'
    ---
    >             '{0}s total / {1} loops -> '
    >             '{2}s per loop for fib({3}) -> {4}'.format(
    >                 elapsed_time,
    >                 number,
    >                 elapsed_time / number,
    >                 n,
    >                 fib(n),
    >             )
    (jupy) doj at sbc:~/20171026$ ./fibpypy.py 0 1 2 3 4 5 6 7 11111
    0.00112700462341s total / 1000 loops -> 1.12700462341e-06s per loop for fib(0) -> 0
    0.00417494773865s total / 1000 loops -> 4.17494773865e-06s per loop for fib(1) -> 1
    0.00802302360535s total / 1000 loops -> 8.02302360535e-06s per loop for fib(2) -> 1
    0.00941896438599s total / 1000 loops -> 9.41896438599e-06s per loop for fib(3) -> 2
    0.0132009983063s total / 1000 loops -> 1.32009983063e-05s per loop for fib(4) -> 3
    0.011430978775s total / 1000 loops -> 1.1430978775e-05s per loop for fib(5) -> 5
    0.0093469619751s total / 1000 loops -> 9.3469619751e-06s per loop for fib(6) -> 8
    0.00933718681335s total / 1000 loops -> 9.33718681335e-06s per loop for fib(7) -> 13
    3.84163093567s total / 1000 loops -> 0.00384163093567s per loop for fib(11111) -> 515...489
    (jupy) doj at sbc:~/20171026$ 

It had been a long time since I had looked at tcl.
I think a big virtue of tcl is its smallness.

###############################################################################

making hamming numbers

wp:Smooth number
wp:Hamming numbers
wp:Richard Hamming

wp: prefix means Wikipedia
To get good answers, consider following the advice in the links below.
http://catb.org/~esr/faqs/smart-questions.html
http://web.archive.org/web/20090627155454/www.greenend.org.uk/rjk/2000/06/14/quoting.html

My first version is correct, but gobbles memory like crazy,
much much worse than a naive recursive fibonacci function.
It starts swapping soon, at which point all hope is lost.

    doj at sbc:~/20171026$ cat ham1.py 
    #!/usr/bin/env python3

    import sys
    from itertools import islice

    def ham(x=1):
        yield x
        g2 = ham(2 * x)
        g3 = ham(3 * x)
        g5 = ham(5 * x)
        x2 = next(g2)
        x3 = next(g3)
        x5 = next(g5)
        while True:
            x = min(x2, x3, x5)
            yield x
            if x2 == x:
                x2 = next(g2)
            if x3 == x:
                x3 = next(g3)
            if x5 == x:
                x5 = next(g5)

    def nth_hamming_number(n):
        return list(islice(ham(), n-1, n))[0]

    def main():
        for arg in sys.argv[1:]:
            n = int(arg)
            x = nth_hamming_number(n)
            print(n, x)

    if __name__ == '__main__':
        main()
    doj at sbc:~/20171026$ 

    doj at sbc:~/20171026$ time ./ham1.py 1
    1 1

    real    0m0.057s
    user    0m0.044s
    sys     0m0.012s
    doj at sbc:~/20171026$ time ./ham1.py 10
    10 12

    real    0m0.058s
    user    0m0.048s
    sys     0m0.012s
    doj at sbc:~/20171026$ time ./ham1.py 100
    100 1536

    real    0m0.087s
    user    0m0.072s
    sys     0m0.012s
    doj at sbc:~/20171026$ time ./ham1.py 200
    200 16200

    real    0m0.429s
    user    0m0.384s
    sys     0m0.044s
    doj at sbc:~/20171026$ time ./ham1.py 300
    300 82944

    real    0m2.950s
    user    0m2.696s
    sys     0m0.244s
    doj at sbc:~/20171026$ time ./ham1.py 400
    400 311040

    real    0m12.706s
    user    0m11.792s
    sys     0m0.884s
    doj at sbc:~/20171026$ time ./ham1.py 500
    500 937500

    real    0m41.093s
    user    0m38.336s
    sys     0m2.672s
    doj at sbc:~/20171026$ time ./ham1.py 600
    
    this was killed after a long time of swapping

Second version tries to avoid duplication,
so is much faster and uses much much less memory.
Seems to be fast enough for the 1000000th hamming number.
It even seems to be correct.
I wonder about using a decorator to avoid having the global dictionary.

    doj at sbc:~/20171026$ cat ham2.py 
    #!/usr/bin/env python3

    import sys
    from itertools import islice

    already_done = set()

    def ham(x=1):
        global already_done

        if x in already_done:
            return
        already_done |= {x}
        yield x

        x_from_generators = {}
        generators = (ham(prime * x) for prime in (2, 3, 5))
        for g in generators:
            try:
                x_from_generators[g] = next(g)
            except StopIteration:
                pass

        while x_from_generators:
            x_min = min(x_from_generators.values())
            yield x_min
            for g, x in x_from_generators.items():
                if x != x_min:
                    continue

                try:
                    x_from_generators[g] = next(g)
                except StopIteration:
                    x_from_generators.pop(g)


    def nth_hamming_number(n):
        return list(islice(ham(), n-1, n))[0]

    def main():
        for arg in sys.argv[1:]:
            n = int(arg)
            x = nth_hamming_number(n)
            print(n, x)

    if __name__ == '__main__':
        main()
    doj at sbc:~/20171026$ 

    doj at sbc:~/20171026$ time ./ham2.py 1
    1 1

    real    0m0.055s
    user    0m0.036s
    sys     0m0.020s
    doj at sbc:~/20171026$ time ./ham2.py 10
    10 12

    real    0m0.057s
    user    0m0.048s
    sys     0m0.004s
    doj at sbc:~/20171026$ time ./ham2.py 100
    100 1536

    real    0m0.061s
    user    0m0.048s
    sys     0m0.012s
    doj at sbc:~/20171026$ time ./ham2.py 1000
    1000 51200000

    real    0m0.111s
    user    0m0.080s
    sys     0m0.028s
    doj at sbc:~/20171026$ time ./ham2.py 10000
    10000 288325195312500000

    real    0m1.115s
    user    0m1.080s
    sys     0m0.032s
    doj at sbc:~/20171026$ time ./ham2.py 100000
    100000 290142196707511001929482240000000000000

    real    0m23.579s
    user    0m23.332s
    sys     0m0.200s
    doj at sbc:~/20171026$ time ./ham2.py 1000000
    1000000 519312780448388736089589843750000000000000000000000000000000000000000000000000000000

    real    8m31.437s
    user    8m27.944s
    sys     0m2.252s
    doj at sbc:~/20171026$ 

From jep200404 at columbus.rr.com  Sat Oct 21 01:11:18 2017
From: jep200404 at columbus.rr.com (jep200404 at columbus.rr.com)
Date: Sat, 21 Oct 2017 01:11:18 -0400
Subject: [CentralOH] 
 =?utf-8?b?MjAxNy0xMC0yMCDnh5XmnIggTHVuY2ggUGxhY2Vt?=
 =?utf-8?q?at_Scribbles=3A_Simplified_Code_Making_It_More_Readable?=
In-Reply-To: <20171020222422.124f124b.jep200404@columbus.rr.com>
References: <20171020222422.124f124b.jep200404@columbus.rr.com>
Message-ID: <20171021011118.5867fb40.jep200404@columbus.rr.com>

On Fri, 20 Oct 2017 22:24:22 -0400, jep200404 at columbus.rr.com wrote:

>     tcl braces
>     versus python
>     fibonacci and hamming numbers

I simplified the tcl and Python fibonacci programs.
Readability was improved.

    (jupy) doj at sbc:~/20171020$ cat fib-no-braces.tcl
    proc fib {n} {
       set a 0
       set b 1
       for {set i 0} {$i < $n} {incr i} {
          set c [expr $a + $b]
          set a $b
          set b $c
       }
       return $a
    }

    puts "Please enter seed value:"

    gets stdin x

    set StartTime [clock microseconds]
    set Answer [fib $x]
    set EndTime [clock microseconds]
    puts "Seed $x; Result $Answer"
    puts "Duration [expr $EndTime - $StartTime] microseconds"
    (jupy) doj at sbc:~/20171020$ 
    (jupy) doj at sbc:~/20171020$ diff FibForXNoBraces.tcl fib-no-braces.tcl
    1,16c1,7
    < proc Fib {n} {
    < 
    <    if {$n == 0} {
    <       set Ret_Value 0
    <    } else {
    <       if {$n < 3} {
    <          set Ret_Value 1
    <       } else {
    <          set PrevVal 1
    <          set ThisVal 1
    <          for {set y 3} {$y <= $n} {incr y} {
    <             set Ret_Value [expr $PrevVal + $ThisVal]
    <             set PrevVal $ThisVal
    <             set ThisVal $Ret_Value
    <          }
    <       }
    ---
    > proc fib {n} {
    >    set a 0
    >    set b 1
    >    for {set i 0} {$i < $n} {incr i} {
    >       set c [expr $a + $b]
    >       set a $b
    >       set b $c
    18,20c9
    < 
    <    return $Ret_Value
    < 
    ---
    >    return $a
    28c17
    < set Answer [Fib $x]
    ---
    > set Answer [fib $x]
    (jupy) doj at sbc:~/20171020$ 

    ###########################################################################

    (jupy) doj at sbc:~/20171020$ cat fib-with-braces.tcl
    proc fib {n} {
       set a 0
       set b 1
       for {set i 0} {$i < $n} {incr i} {
          set c [expr {$a + $b}]
          set a $b
          set b $c
       }
       return $a
    }

    puts "Please enter seed value:"

    gets stdin x

    set StartTime [clock microseconds]
    set Answer [fib $x]
    set EndTime [clock microseconds]
    puts "Seed $x; Result $Answer"
    puts "Duration [expr $EndTime - $StartTime] microseconds"
    (jupy) doj at sbc:~/20171020$ 
    (jupy) doj at sbc:~/20171020$ diff fib-no-braces.tcl fib-with-braces.tcl
    5c5
    <       set c [expr $a + $b]
    ---
    >       set c [expr {$a + $b}]
    (jupy) doj at sbc:~/20171020$ 

    ###########################################################################

    (jupy) doj at sbc:~/20171020$ cat fib2.py 
    #!/usr/bin/env python3

    import sys
    from timeit import timeit

    source_code = '''
    def fib(n):
        a, b = 0, 1
        for _ in range(n):
            a, b = b, a + b
        return a
    '''

    exec(source_code)

    def main():
        for arg in sys.argv[1:]:
            n = int(arg)
            number = 1000
            elapsed_time = timeit('fib(%s)' % n, setup=source_code, number=number)
            print(
                f'{elapsed_time}s total / {number} loops -> '
                f'{elapsed_time / number}s per loop for fib({n}) -> {fib(n)}'
            )

    if __name__ == '__main__':
        main()
    (jupy) doj at sbc:~/20171020$ diff fib.py fib2.py
    8,9d7
    <     if n == 0:
    <         return 0
    (jupy) doj at sbc:~/20171020$ 

    ###########################################################################

As expected, those changes had negligible effects on the exection times.

    (jupy) doj at sbc:~/20171020$ echo 11111 | tclsh fib-no-braces.tcl
    Please enter seed value:
    Seed 11111; Result 515...489
    Duration 129060134 microseconds
    (jupy) doj at sbc:~/20171020$ 

    ###########################################################################

    (jupy) doj at sbc:~/20171020$ echo 11111 | tclsh fib-with-braces.tcl
    Please enter seed value:
    Seed 11111; Result 515...489
    Duration 43387 microseconds
    (jupy) doj at sbc:~/20171020$ 

    ###########################################################################

    (jupy) doj at sbc:~/20171020$ ./fib2.py 0 1 2 3 4 5 6 7 11111
    0.0012247690001458977s total / 1000 loops -> 1.2247690001458977e-06s per loop for fib(0) -> 0
    0.0017716410002321936s total / 1000 loops -> 1.7716410002321935e-06s per loop for fib(1) -> 1
    0.0018954030001623323s total / 1000 loops -> 1.8954030001623324e-06s per loop for fib(2) -> 1
    0.002083211000353913s total / 1000 loops -> 2.0832110003539127e-06s per loop for fib(3) -> 2
    0.002242174000457453s total / 1000 loops -> 2.242174000457453e-06s per loop for fib(4) -> 3
    0.002450655999382434s total / 1000 loops -> 2.450655999382434e-06s per loop for fib(5) -> 5
    0.002553395000177261s total / 1000 loops -> 2.5533950001772608e-06s per loop for fib(6) -> 8
    0.003030005000255187s total / 1000 loops -> 3.030005000255187e-06s per loop for fib(7) -> 13
    8.490469498000493s total / 1000 loops -> 0.008490469498000494s per loop for fib(11111) -> 515...489
    (jupy) doj at sbc:~/20171020$ 

From jmknapp at gmail.com  Sat Oct 21 20:23:12 2017
From: jmknapp at gmail.com (Joe Knapp)
Date: Sat, 21 Oct 2017 20:23:12 -0400
Subject: [CentralOH] 
	=?utf-8?b?MjAxNy0xMC0yMCDnh5XmnIggTHVuY2ggUGxhY2Vt?=
	=?utf-8?q?at_Scribbles=3A_tcl_braces_versus_python=3B_fibonacci_ve?=
	=?utf-8?q?rsus_hamming?=
In-Reply-To: <20171020222422.124f124b.jep200404@columbus.rr.com>
References: <20171020222422.124f124b.jep200404@columbus.rr.com>
Message-ID: <CALwn+dbO9f5rMZMeZJHoFH3tLVChK5ZdBh+oNNwYt908sEiqyw@mail.gmail.com>

On Fri, Oct 20, 2017 at 10:24 PM, <jep200404 at columbus.rr.com> wrote:

>
> ############################################################
> ###################
>
> making hamming numbers
>
> wp:Smooth number
> wp:Hamming numbers
> wp:Richard Hamming
>

One to add is:

wp:Regular number

That deals with 5-smooth numbers specifically. I think the term was coined
by someone studying Babylonian (base 60) mathematics, which only allows
division by such "regular" numbers. They also come up in music theory
(intervals between notes in the 'just' tuning scheme).


> Second version tries to avoid duplication,
> so is much faster and uses much much less memory.
> Seems to be fast enough for the 1000000th hamming number.
> It even seems to be correct.
> ...
>     doj at sbc:~/20171026$ time ./ham2.py 1000000
>     1000000 519312780448388736089589843750000000000000000000000000000000
> 000000000000000000000000
>
>     real    8m31.437s
>     user    8m27.944s
>     sys     0m2.252s
>

Not sure of the state of the art, but check out this old Dr. Dobbs article
(2008):

http://www.drdobbs.com/architecture-and-design/hamming-problem/228700538

They report a Lisp version that took 900 seconds to generate 127 million
Hamming numbers.

A lot people skip trying to calculate the entire sequence up to the nth
Hamming number, instead just finding the nth number alone, using an
algorithm described in the Dr, Dobbs article .

This page:

https://rosettacode.org/wiki/Hamming_numbers

...has a lot of implementations in different languages, but most are of the
"just give the nth number" variety.

Joe
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From jep200404 at columbus.rr.com  Sat Oct 21 22:50:55 2017
From: jep200404 at columbus.rr.com (jep200404 at columbus.rr.com)
Date: Sat, 21 Oct 2017 22:50:55 -0400
Subject: [CentralOH] One Change Too Far: Got Rid of Temporary Variable
In-Reply-To: <20171021011118.5867fb40.jep200404@columbus.rr.com>
References: <20171020222422.124f124b.jep200404@columbus.rr.com>
 <20171021011118.5867fb40.jep200404@columbus.rr.com>
Message-ID: <20171021225055.1a679c71.jep200404@columbus.rr.com>

On Sat, 21 Oct 2017 01:11:18 -0400, jep200404 at columbus.rr.com wrote:

>           set c [expr $a + $b]
>           set a $b
>           set b $c

Below: One change too far:

    Get rid of the temporary variable c that is above.

It is interesting that it can be done at all.
But golly, it sure is hard to understand how the program works now.
The extra calculation also makes the program slower
than the one that used the temporary variable.

Also uses shebang.

    doj at sbc:~/20171020$ cat fib-without-c.tcl
    #!/usr/bin/env tclsh

    proc fib {n} {
       set a 0
       set b 1
       for {set i 0} {$i < $n} {incr i} {
          set b [expr {$a + $b}]
          set a [expr {$b - $a}]
       }
       return $a
    }

    puts "Please enter seed value:"

    gets stdin x

    set StartTime [clock microseconds]
    set Answer [fib $x]
    set EndTime [clock microseconds]
    puts "Seed $x; Result $Answer"
    puts "Duration [expr $EndTime - $StartTime] microseconds"
    doj at sbc:~/20171020$ 

    doj at sbc:~/20171020$ diff fib-with-braces.tcl fib-without-c.tcl
    7,9c7,8
    <       set c [expr {$a + $b}]
    <       set a $b
    <       set b $c
    ---
    >       set b [expr {$a + $b}]
    >       set a [expr {$b - $a}]
    doj at sbc:~/20171020$ 

    doj at sbc:~/20171020$ echo 11111 | time ./fib-without-c.tcl
    Please enter seed value:
    Seed 11111; Result 515...489
    Duration 81068 microseconds
    0.11user 0.00system 0:00.11elapsed 97%CPU (0avgtext+0avgdata 4940maxresident)k
    0inputs+0outputs (0major+356minor)pagefaults 0swaps
    doj at sbc:~/20171020$ 

From jep200404 at columbus.rr.com  Sat Oct 21 23:05:38 2017
From: jep200404 at columbus.rr.com (jep200404 at columbus.rr.com)
Date: Sat, 21 Oct 2017 23:05:38 -0400
Subject: [CentralOH] Generalized ham() to smooth()
In-Reply-To: <20171020222422.124f124b.jep200404@columbus.rr.com>
References: <20171020222422.124f124b.jep200404@columbus.rr.com>
Message-ID: <20171021230538.0f9b19f5.jep200404@columbus.rr.com>

On Fri, 20 Oct 2017 22:24:22 -0400, jep200404 at columbus.rr.com wrote:

> Second version tries to avoid duplication,
> so is much faster and uses much much less memory.
> Seems to be fast enough for the 1000000th hamming number.
> It even seems to be correct.
> I wonder about using a decorator to avoid having the global dictionary.
> 
>     doj at sbc:~/20171026$ cat ham2.py 

The ham() generator function from ham2.py
has been generalized to smooth() in ham4.py below.
Also, the annoying global has been eliminated.
Surprisingly, the speed is very similar to previous versions.

The hamming() function is just a thin wrapper around smooth().

    doj at sbc:~/20171020$ cat ham4.py 
    #!/usr/bin/env python3

    import sys
    from itertools import islice


    def smooth(x, primes, already_done):
        if x in already_done:
            return
        already_done |= {x}
        yield x

        x_from_generators = {}
        generators = (
            smooth(prime * x, primes, already_done)
            for prime in primes
        )
        for g in generators:
            try:
                x_from_generators[g] = next(g)
            except StopIteration:
                pass

        while x_from_generators:
            x_min = min(x_from_generators.values())
            yield x_min
            for g, x in x_from_generators.items():
                if x != x_min:
                    continue

                try:
                    x_from_generators[g] = next(g)
                except StopIteration:
                    x_from_generators.pop(g)


    def hamming():
        yield from smooth(x=1, primes=(2, 3, 5), already_done=set())


    def nth_hamming_number(n):
        return list(islice(hamming(), n-1, n))[0]


    def main():
        for arg in sys.argv[1:]:
            n = int(arg)
            x = nth_hamming_number(n)
            print(n, x)

    if __name__ == '__main__':
        main()
    doj at sbc:~/20171020$ 

    doj at sbc:~/20171020$ time ./ham4.py 1
    1 1

    real    0m0.054s
    user    0m0.032s
    sys     0m0.020s
    doj at sbc:~/20171020$ time ./ham4.py 10
    10 12

    real    0m0.056s
    user    0m0.048s
    sys     0m0.008s
    doj at sbc:~/20171020$ time ./ham4.py 100
    100 1536

    real    0m0.058s
    user    0m0.048s
    sys     0m0.004s
    doj at sbc:~/20171020$ time ./ham4.py 1000
    1000 51200000

    real    0m0.112s
    user    0m0.088s
    sys     0m0.024s
    doj at sbc:~/20171020$ time ./ham4.py 10000
    10000 288325195312500000

    real    0m1.141s
    user    0m1.112s
    sys     0m0.020s
    doj at sbc:~/20171020$ time ./ham4.py 100000
    100000 290142196707511001929482240000000000000

    real    0m23.773s
    user    0m23.524s
    sys     0m0.200s
    doj at sbc:~/20171020$ time ./ham4.py 1000000
    1000000 519312780448388736089589843750000000000000000000000000000000000000000000000000000000

    real    8m27.888s
    user    8m23.132s
    sys     0m2.724s
    doj at sbc:~/20171020$

From jep200404 at columbus.rr.com  Sun Oct 22 06:42:16 2017
From: jep200404 at columbus.rr.com (jep200404 at columbus.rr.com)
Date: Sun, 22 Oct 2017 06:42:16 -0400
Subject: [CentralOH] =?utf-8?q?2017-10-19_=E9=81=93=E5=A0=B4_Scribbles_?=
 =?utf-8?b?76SY5pu4L+aDoeaWhz8gdmVyc2lvbiBzaGliYm9sZXRoOyBicmFjZXMgaW4g?=
 =?utf-8?q?python=3B_pyflakes=3B_jedi=3B_breaking_out_of_nested_loops=3B_a?=
 =?utf-8?q?scii_art=3B_recursion_palooza_ioccc=3B_jupyter_notebook=3B_avoi?=
 =?utf-8?q?ding_sql_injection_attacks=3B_csv=3B_recursion=3B_fibonacci?=
Message-ID: <20171022064216.26290187.jep200404@columbus.rr.com>

many folks tonight

Python version shibboleth: '...' versus '!'

    doj at sbc:~$ python
    Python 2.7.12 (default, Nov 19 2016, 06:48:10)
    [GCC 5.4.0 20160609] on linux2
    Type "help", "copyright", "credits" or "license" for more information.
    >>> import __hello__
    Hello world...
    >>>
    doj at sbc:~$

    doj at sbc:~$ python3
    Python 3.5.2 (default, Sep 14 2017, 22:51:06)
    [GCC 5.4.0 20160609] on linux
    Type "help", "copyright", "credits" or "license" for more information.
    >>> import __hello__
    Hello world!
    >>>
    doj at sbc:~$

car needs fixed versus car needs to be fixed

pop versus soda versus coke
http://bigthink.com/strange-maps/308-the-pop-vs-soda-map
https://laughingsquid.com/soda-pop-or-coke-maps-of-regional-dialect-variation-in-the-united-states/
http://www.mappery.com/Pop-vs-Soda-US-Map

Perl is 30 years old around now.
It surprised me that Perl is only four years older than Python.

How to use braces instead of indentation to indicate structure.
Python indentation
https://en.wikipedia.org/wiki/Python_syntax_and_semantics#Indentation

    doj at sbc:~$ python2
    Python 2.7.12 (default, Nov 19 2016, 06:48:10)
    [GCC 5.4.0 20160609] on linux2
    Type "help", "copyright", "credits" or "license" for more information.
    >>> from __future__ import braces
      File "<stdin>", line 1
    SyntaxError: not a chance
    >>>
    doj at sbc:~$

    doj at sbc:~$ python3
    Python 3.5.2 (default, Sep 14 2017, 22:51:06)
    [GCC 5.4.0 20160609] on linux
    Type "help", "copyright", "credits" or "license" for more information.
    >>> from __future__ import braces
      File "<stdin>", line 1
    SyntaxError: not a chance
    >>>
    doj at sbc:~$

pyflakes
jedi

Someone asked about breaking out of nested loops. Study:

    http://nbviewer.jupyter.org/github/cohpy/challenge-201605-generators/blob/master/james-prior/b-break-out-of-nested-loops.ipynb
    http://nbviewer.jupyter.org/github/james-prior/cohpy/blob/master/20160708-dojo-breaking-out-of-nested-loops-to-variable-levels.ipynb

    2016-07-08 ?? Scribbles ??/??? input() from io.StringIO() csv try/except EAFP LBYL regexes xterm links scarf mitigation java ee rice libreoffice defect rate machine learning identity warranty stickers eye tracking breaking nested loops books buildozer kivy sed & awk iter(partial(input, prompt), 'quit') bash in ms windows ! in.format() loop unrolling parade
    https://mail.python.org/pipermail/centraloh/2016-July/002895.html

    2016-07-15 ?? Scribbles ??/??? atlassian diff regex tiobe 5*7*17 try/except/break/goto kivy pylint pyflakes jedi Magnolia Thunderpussy Pok?mon Go hackerrank smell wipy iot natron indentation LBM
    https://mail.python.org/pipermail/centraloh/2016-July/002901.html

How to use an Arduino and Raspberry Pi to turn a fiber optic neural network into wall art
https://opensource.com/article/17/10/fiber-optic-neural-network-art

Learn how to program in Python by building a simple dice game
https://opensource.com/article/17/10/python-101

ascii art way before ascii
https://upload.wikimedia.org/wikipedia/commons/7/78/Brooklyn-Daily-Eagle-1875-01-06.png

wp:IOCCC
august entry of 1985 http://ioccc.org/years.html#1985
recursion palooza
fans of recursion should figure out the following

    http://ioccc.org/1985/august/august.c

wp: prefix means Wikipedia
To get good answers, consider following the advice in the links below.
http://catb.org/~esr/faqs/smart-questions.html
http://web.archive.org/web/20090627155454/www.greenend.org.uk/rjk/2000/06/14/quoting.html

Meet Bill Pollock, founder of No Starch Press
https://opensource.com/article/17/10/no-starch
https://www.nostarch.com/catalog/python

The Python 3 Standard Library by Example
by Doug Hellmann

anki monkey patching wrap

wp:"Hello, World!" program

conda create --yes --name erik2 python=2 jupyter
source activate erik2
jupyter notebook --browser=firefox

conda create --yes --name erik3 python=3 jupyter
source activate erik3
jupyter notebook --browser=firefox

https://xkcd.com/327/

PEP 249 -- Python Database API Specification v2.0
https://www.python.org/dev/peps/pep-0249/

django

CSV File Reading and Writing
https://docs.python.org/3/library/csv.html

wp:recursion
wp:Fibonacci number

From dallascboys413 at gmail.com  Mon Oct 23 09:55:02 2017
From: dallascboys413 at gmail.com (Jacob Escobedo)
Date: Mon, 23 Oct 2017 09:55:02 -0400
Subject: [CentralOH] Beginner python user
In-Reply-To: <CAAOWqTVcEAovRuXWM4whGKWe9R_miRFF1or1sMJKwZaE8Lhk9A@mail.gmail.com>
References: <CAAOWqTVq2AO+w6xxuksfT9NYCgfCK=Rhh8JNs2JURyE9NfbuCQ@mail.gmail.com>
 <CAAOWqTUKP-S3CU4CyoJAo44THv2dCpVAu02for1LXccFhdB=Wg@mail.gmail.com>
 <CAAOWqTVzzXfr0UawPPRmHPOXS-E8ZU=iQmUGHme4TfzRNmUVCQ@mail.gmail.com>
 <CAAOWqTVX6fCSuby9z9bDTvxw5Ue8nbv4FTTm=SQtrEDnOtDJvA@mail.gmail.com>
 <CAAOWqTWLEkZF_xc5fNCSbFVOvhnB--WJWrDAqDcSFWH=wFB1hA@mail.gmail.com>
 <CAAOWqTWzQ63oz_sXEPvX5uNSXm7oVsX8FEb9aJf5o4ZKXZd2Pg@mail.gmail.com>
 <CAAOWqTUCVQpPVSGwXhjrRY-9gLZKMsFvUsWnDeC0Tyv-aXSimA@mail.gmail.com>
 <CAAOWqTXq=61pawPpkbzwdCxTyWa+O+_dJRQK5bJ6ktvEWPQq0A@mail.gmail.com>
 <CAAOWqTVhdebU-0=4feFNU=sUOkDi70svKsRAimhiFEqQR-BJXg@mail.gmail.com>
 <CAAOWqTXgbdAEvC5_iNciw=sv5D42_43WMsNdbUf8Ug3Q6b_unw@mail.gmail.com>
 <20171005124451.3d038f17.jep200404@columbus.rr.com>
 <CAAOWqTVcEAovRuXWM4whGKWe9R_miRFF1or1sMJKwZaE8Lhk9A@mail.gmail.com>
Message-ID: <CAAOWqTUHTq24BemY6jcJgaZazFi7eXxNTngyy1sOZqaB6uU78A@mail.gmail.com>

Hello everyone again,


I wanted to see if there was anyone or multiple people that are on the web
development side that would be interested or able to meet up with me this
weekend for like an hr or so, so I can ask some questions and get advice .


Thanks again,

Jacob

On Oct 5, 2017 4:51 PM, "Jacob Escobedo" <dallascboys413 at gmail.com> wrote:

> Ok awesome I'll try to make it to all of those, unfortunately I can't
> tonight.
>
> Jacob
>
> On Oct 5, 2017 12:45 PM, <jep200404 at columbus.rr.com> wrote:
>
>> On Thu, 5 Oct 2017 07:23:06 -0400, Jacob Escobedo <
>> dallascboys413 at gmail.com> wrote:
>>
>> > I would love to meet some people not only during the meetups but
>> outside of
>> > it so I can pick your brain asking questions and other things to help me
>> > along my way.
>>
>> The weekly dojos are the place for exactly that.
>> There is one tonight. See cohpy.org.
>> _______________________________________________
>> CentralOH mailing list
>> CentralOH at python.org
>> https://mail.python.org/mailman/listinfo/centraloh
>>
>
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From jmknapp at gmail.com  Mon Oct 23 14:09:14 2017
From: jmknapp at gmail.com (Joe Knapp)
Date: Mon, 23 Oct 2017 14:09:14 -0400
Subject: [CentralOH] 
	=?utf-8?b?MjAxNy0xMC0yMCDnh5XmnIggTHVuY2ggUGxhY2Vt?=
	=?utf-8?q?at_Scribbles=3A_tcl_braces_versus_python=3B_fibonacci_ve?=
	=?utf-8?q?rsus_hamming?=
In-Reply-To: <20171020222422.124f124b.jep200404@columbus.rr.com>
References: <20171020222422.124f124b.jep200404@columbus.rr.com>
Message-ID: <CALwn+daPUtneE9AMePxRPqSAFwVxtRCjFKudkmRVWMKp9CUeyg@mail.gmail.com>

Re: Hamming numbers

I tried a somewhat different approach to generating the Hamming sequence,
based on classifying the intervals from one number to the next, i.e., the
interval from 1 to 2 is 2/1 (2.0), from 2 to 3 is 3/2 (1.5)... from 1536
(the 100th Hamming number) to 1600 is 5^2/2^3 (1.08). It turns out that
there is only a very limited number of discrete intervals from one Hamming
number to the next in quite a large range. E.g., for the first 1.59
trillion Hamming numbers there are only 119 different intervals, each
identified by an i,j,k triple where i,j,k are positive or negative
integers. The example above for the 100th-101st interval is {-3,0,2}.

As the Hamming number goes up the interval to the next one tends to go
down, which makes sense because there are more possibilities that some
combination of i,j,k will result in a fraction close to 1.0.

Anyway, here's a C header file with the table in the struct hamtab[]:

https://github.com/jmknapp/hammingnumbers/blob/master/hamseq.h

So given a Hamming number with exponents {i,j,k}, to find the next number
just look through the table for the first entry having {p2,p3,p5} such that
i+p2 > 0 && j+p3 > 0 && i+p5 > 0 (since multiplication would just be adding
the exponents). Voila! At most 119 entries have to be checked and only
short int additions and comparisons are involved.

That goes pretty fast, but a significant speedup (about a factor of 4 or 5)
can come from not necessarily searching the table from the 0th index. The
second struct in the header file shows a successor table (succtab[]) that
has lists of all possible successors of each entry (just found empirically
by running through the sequence once).

This C code along with the header file implements the algorithm:

https://github.com/jmknapp/hammingnumbers/blob/master/hamseq.c

compiled with: gcc -std=c99 -O3 hamseq.c -o hamseq

The attached plot shows the execution time on an i7-2600 3.4GHz machine--it
takes about 2 seconds to generate the first 100 million Hamming numbers and
several hours for the first trillion.

I was thinking of porting this to python to see how it would go, but have a
learning curve there. Would be a lot slower except maybe with pypy?

Joe
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From amyngbedinghaus at gmail.com  Mon Oct 23 12:44:31 2017
From: amyngbedinghaus at gmail.com (Amy Bedinghaus)
Date: Mon, 23 Oct 2017 12:44:31 -0400
Subject: [CentralOH] Beginner python user
In-Reply-To: <CAAOWqTU16LeM7KMAHuU=jSRCK9SX+SS6rw6ev55ANS=Af3HPLA@mail.gmail.com>
References: <CAAOWqTVq2AO+w6xxuksfT9NYCgfCK=Rhh8JNs2JURyE9NfbuCQ@mail.gmail.com>
 <CAAOWqTUKP-S3CU4CyoJAo44THv2dCpVAu02for1LXccFhdB=Wg@mail.gmail.com>
 <CAAOWqTVzzXfr0UawPPRmHPOXS-E8ZU=iQmUGHme4TfzRNmUVCQ@mail.gmail.com>
 <CAAOWqTVX6fCSuby9z9bDTvxw5Ue8nbv4FTTm=SQtrEDnOtDJvA@mail.gmail.com>
 <CAAOWqTWLEkZF_xc5fNCSbFVOvhnB--WJWrDAqDcSFWH=wFB1hA@mail.gmail.com>
 <CAAOWqTWzQ63oz_sXEPvX5uNSXm7oVsX8FEb9aJf5o4ZKXZd2Pg@mail.gmail.com>
 <CAAOWqTUCVQpPVSGwXhjrRY-9gLZKMsFvUsWnDeC0Tyv-aXSimA@mail.gmail.com>
 <CAAOWqTXq=61pawPpkbzwdCxTyWa+O+_dJRQK5bJ6ktvEWPQq0A@mail.gmail.com>
 <CAAOWqTVhdebU-0=4feFNU=sUOkDi70svKsRAimhiFEqQR-BJXg@mail.gmail.com>
 <CAAOWqTXgbdAEvC5_iNciw=sv5D42_43WMsNdbUf8Ug3Q6b_unw@mail.gmail.com>
 <CAOoMBVjRW=K7Agmw4WFS2Jr9ewrp_DsyYz5A4VsH708LFzbXCQ@mail.gmail.com>
 <CAAOWqTU16LeM7KMAHuU=jSRCK9SX+SS6rw6ev55ANS=Af3HPLA@mail.gmail.com>
Message-ID: <CAHkbLOzam4i941JTM1jn4NC2GDWPkYSLyC2VfCow8jaaiX7V5Q@mail.gmail.com>

Hi Jacob, I also want to learn Python, and I also am primarily
knowledgeable about web development.  I'd love to talk strategy about how
to get started with you.  See you this Thursday at the dojo at Smokehouse?
-Amy

Amy Bedinghaus, MA
(864) 381-1830


On Thu, Oct 5, 2017 at 11:33 AM, Jacob Escobedo <dallascboys413 at gmail.com>
wrote:

> Yeah I'm leaning towards web development, but since I am new I'm not only
> focusing on that because I don't know what I enjoy doing yet.
>
>
> Jacob
>
> On Oct 5, 2017 10:45 AM, "pybokeh" <pybokeh at gmail.com> wrote:
>
>> I'm in Dublin also.  I can help when I can.  But, if you're primarily
>> interested in web development, I would suggest getting help from others.  I
>> only have basic knowledge in web dev.  My domain knowledge is in data
>> analysis or data science.  It would help if you tell us what you want to
>> use Python for.  I understand if you don't know at this moment, but would
>> help in narrowing the focus.  Python can be used for a lot of things.
>>
>> - Daniel
>> pybokeh at gmail.com
>>
>>
>> On Oct 5, 2017 9:39 AM, "Jacob Escobedo" <dallascboys413 at gmail.com>
>> wrote:
>>
>> Hello everyone,
>>
>> I have just started to dip my toes into python and I am looking for
>> mentors and peers to help me learn.
>>
>> I am doing some free course and other material I have found online. My
>> goal is to self teach using all these free courses and resources I have
>> found.
>>
>> I would love to meet some people not only during the meetups but outside
>> of it so I can pick your brain asking questions and other things to help me
>> along my way.
>>
>> If you want to be a mentor or any advice that would be awesome.
>>
>> Thank you,
>>
>> Jacob
>>
>> _______________________________________________
>> CentralOH mailing list
>> CentralOH at python.org
>> https://mail.python.org/mailman/listinfo/centraloh
>>
>>
>>
>> _______________________________________________
>> CentralOH mailing list
>> CentralOH at python.org
>> https://mail.python.org/mailman/listinfo/centraloh
>>
>>
> _______________________________________________
> CentralOH mailing list
> CentralOH at python.org
> https://mail.python.org/mailman/listinfo/centraloh
>
>
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From dallascboys413 at gmail.com  Mon Oct 23 16:52:42 2017
From: dallascboys413 at gmail.com (Jacob Escobedo)
Date: Mon, 23 Oct 2017 16:52:42 -0400
Subject: [CentralOH] Beginner python user
In-Reply-To: <CAHkbLOzam4i941JTM1jn4NC2GDWPkYSLyC2VfCow8jaaiX7V5Q@mail.gmail.com>
References: <CAAOWqTVq2AO+w6xxuksfT9NYCgfCK=Rhh8JNs2JURyE9NfbuCQ@mail.gmail.com>
 <CAAOWqTUKP-S3CU4CyoJAo44THv2dCpVAu02for1LXccFhdB=Wg@mail.gmail.com>
 <CAAOWqTVzzXfr0UawPPRmHPOXS-E8ZU=iQmUGHme4TfzRNmUVCQ@mail.gmail.com>
 <CAAOWqTVX6fCSuby9z9bDTvxw5Ue8nbv4FTTm=SQtrEDnOtDJvA@mail.gmail.com>
 <CAAOWqTWLEkZF_xc5fNCSbFVOvhnB--WJWrDAqDcSFWH=wFB1hA@mail.gmail.com>
 <CAAOWqTWzQ63oz_sXEPvX5uNSXm7oVsX8FEb9aJf5o4ZKXZd2Pg@mail.gmail.com>
 <CAAOWqTUCVQpPVSGwXhjrRY-9gLZKMsFvUsWnDeC0Tyv-aXSimA@mail.gmail.com>
 <CAAOWqTXq=61pawPpkbzwdCxTyWa+O+_dJRQK5bJ6ktvEWPQq0A@mail.gmail.com>
 <CAAOWqTVhdebU-0=4feFNU=sUOkDi70svKsRAimhiFEqQR-BJXg@mail.gmail.com>
 <CAAOWqTXgbdAEvC5_iNciw=sv5D42_43WMsNdbUf8Ug3Q6b_unw@mail.gmail.com>
 <CAOoMBVjRW=K7Agmw4WFS2Jr9ewrp_DsyYz5A4VsH708LFzbXCQ@mail.gmail.com>
 <CAAOWqTU16LeM7KMAHuU=jSRCK9SX+SS6rw6ev55ANS=Af3HPLA@mail.gmail.com>
 <CAHkbLOzam4i941JTM1jn4NC2GDWPkYSLyC2VfCow8jaaiX7V5Q@mail.gmail.com>
Message-ID: <CAAOWqTWksM+FCtW1uUwiYt9QiHYyjBVRDxoJsodcG1rQdUqGKw@mail.gmail.com>

Yeah definitely I will see you there.

On Oct 23, 2017 2:24 PM, "Amy Bedinghaus" <amyngbedinghaus at gmail.com> wrote:

> Hi Jacob, I also want to learn Python, and I also am primarily
> knowledgeable about web development.  I'd love to talk strategy about how
> to get started with you.  See you this Thursday at the dojo at Smokehouse?
> -Amy
>
> Amy Bedinghaus, MA
> (864) 381-1830
>
>
> On Thu, Oct 5, 2017 at 11:33 AM, Jacob Escobedo <dallascboys413 at gmail.com>
> wrote:
>
>> Yeah I'm leaning towards web development, but since I am new I'm not
>> only  focusing on that because I don't know what I enjoy doing yet.
>>
>>
>> Jacob
>>
>> On Oct 5, 2017 10:45 AM, "pybokeh" <pybokeh at gmail.com> wrote:
>>
>>> I'm in Dublin also.  I can help when I can.  But, if you're primarily
>>> interested in web development, I would suggest getting help from others.  I
>>> only have basic knowledge in web dev.  My domain knowledge is in data
>>> analysis or data science.  It would help if you tell us what you want to
>>> use Python for.  I understand if you don't know at this moment, but would
>>> help in narrowing the focus.  Python can be used for a lot of things.
>>>
>>> - Daniel
>>> pybokeh at gmail.com
>>>
>>>
>>> On Oct 5, 2017 9:39 AM, "Jacob Escobedo" <dallascboys413 at gmail.com>
>>> wrote:
>>>
>>> Hello everyone,
>>>
>>> I have just started to dip my toes into python and I am looking for
>>> mentors and peers to help me learn.
>>>
>>> I am doing some free course and other material I have found online. My
>>> goal is to self teach using all these free courses and resources I have
>>> found.
>>>
>>> I would love to meet some people not only during the meetups but outside
>>> of it so I can pick your brain asking questions and other things to help me
>>> along my way.
>>>
>>> If you want to be a mentor or any advice that would be awesome.
>>>
>>> Thank you,
>>>
>>> Jacob
>>>
>>> _______________________________________________
>>> CentralOH mailing list
>>> CentralOH at python.org
>>> https://mail.python.org/mailman/listinfo/centraloh
>>>
>>>
>>>
>>> _______________________________________________
>>> CentralOH mailing list
>>> CentralOH at python.org
>>> https://mail.python.org/mailman/listinfo/centraloh
>>>
>>>
>> _______________________________________________
>> CentralOH mailing list
>> CentralOH at python.org
>> https://mail.python.org/mailman/listinfo/centraloh
>>
>>
>
> _______________________________________________
> CentralOH mailing list
> CentralOH at python.org
> https://mail.python.org/mailman/listinfo/centraloh
>
>
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From jep200404 at columbus.rr.com  Fri Oct 27 02:46:36 2017
From: jep200404 at columbus.rr.com (jep200404 at columbus.rr.com)
Date: Fri, 27 Oct 2017 02:46:36 -0400
Subject: [CentralOH] =?utf-8?q?2017-10-26_=E9=81=93=E5=A0=B4_Scribbles_?=
 =?utf-8?b?76SY5pu4L+aDoeaWhz8gSWRpb21hdGljIExvb3BzOiBpIDwgbiB2ZXJzdXMg?=
 =?utf-8?q?i_=3C=3D_n_-_1=3B_json?=
Message-ID: <20171027024636.21fc7bd7.jep200404@columbus.rr.com>

For terminating loops, i < n is the standard idiom, not i <= n - 1.

One often needs a loop to do something n times.
The most common starting value for a loop variable is 0
to use as an index into arrays.
Hence the value of the loop variable the last time in the body of the loop
will be n - 1. The idiomatic ways of writing such a loop in Python and C are:

    Python: for i in range(n):
    C: for (i = 0; i < n; i++)
    tcl: for {set i 0} {$i < $n} {incr i}

Notice the tests in the C and tcl versions:

    C: i < n
    tcl: $i < $n

The following could be used instead:

    C: i <= n - 1
    tcl $i < $n - 1

For brevity, I will call the i < n versions "lt"
and the i <= n - 1 versions "le".

The le versions require n - 1 to be calculated,
whereas the lt versions can use n as is.
This favors the lt versions.

For signed values in C,
both the lt and le versions can "do nothing" gracefully.
For unsigned values in C, the lt version can "do nothing" gracefully,
but the le version can not "do nothing" gracefully.
Consider the two following C code fragments:

    lt version:

        unsigned n;
        unsigned i;

        for (i = 0; i < n; i++)
            ...

    le version

        unsigned n;
        unsigned i;

        for (i = 0; i <= n - 1; i++)
            ...

    When n is 0, the lt version will correctly execute the body of the
    loop zero times.

    When n is 0, the le version will execute the loop infinitely. When
    n is 0, n - 1 is not -1. Instead n - 1 is the largest possible
    unsigned integer (aka UINT_MAX), so i <= n - 1 will always be true,
    so the loop is infinite.

    Below is an example of this. Study the output.

    doj at sbc:~/20171026$ cat loop.c
    #include <stdlib.h>
    #include <stdio.h>

    void do_n_times(unsigned n)
    {
        unsigned i;

        printf("before lt loop to be done %u times\n", n);
        for (i = 0; i < n; i++)
            printf("inside lt loop i = %u\n", i);
        printf("after lt loop\n");
        printf("before le loop to be done %u times\n", n);
        for (i = 0; i <= n - 1; i++) {
            printf("inside le loop i = %u\n", i);
            if (i == 5U) /* skip over boring middle number */
                i = (-i);
        }
        printf("after le loop\n");
    }

    int main(int argc, char *argv[])
    {
        unsigned i;
        unsigned n;

        do_n_times(1U);
        do_n_times(0U);
    }
    doj at sbc:~/20171026$ ./loop | head -n 30
    before lt loop to be done 1 times
    inside lt loop i = 0
    after lt loop
    before le loop to be done 1 times
    inside le loop i = 0
    after le loop
    before lt loop to be done 0 times
    after lt loop
    before le loop to be done 0 times
    inside le loop i = 0
    inside le loop i = 1
    inside le loop i = 2
    inside le loop i = 3
    inside le loop i = 4
    inside le loop i = 5
    inside le loop i = 4294967292
    inside le loop i = 4294967293
    inside le loop i = 4294967294
    inside le loop i = 4294967295
    inside le loop i = 0
    inside le loop i = 1
    inside le loop i = 2
    inside le loop i = 3
    inside le loop i = 4
    inside le loop i = 5
    inside le loop i = 4294967292
    inside le loop i = 4294967293
    inside le loop i = 4294967294
    inside le loop i = 4294967295
    inside le loop i = 0
    doj at sbc:~/20171026$

Eventually, one learns to normally use the i < n test idiom.
When one see that some other test is being used, one has to scrutinize it.

See page 12 of "The Practice of Programming" by Kernighan & Pike.

###############################################################################

3 Tools to Help You Remember Linux Commands
https://www.linux.com/learn/intro-to-linux/2017/10/3-tools-help-you-remember-linux-commands

More ways to examine network connections on Linux
https://www.networkworld.com/article/3233306/linux/more-ways-to-examine-network-connections-on-linux.html

does it matter at all?
Party Like It's 1987 - PC-MOS/386 Goes Open Source
https://www.lifehacker.com.au/2017/10/party-like-its-1987-pc-mos386-goes-open-source/

How to Encode Data From Python To JSON
https://linuxconfig.org/how-to-encode-data-from-python-to-json

wp:Facter

wp: prefix means Wikipedia
To get good answers, consider following the advice in the links below.
http://catb.org/~esr/faqs/smart-questions.html
http://web.archive.org/web/20090627155454/www.greenend.org.uk/rjk/2000/06/14/quoting.html

From herrold at owlriver.com  Fri Oct 27 11:17:51 2017
From: herrold at owlriver.com (R P Herrold)
Date: Fri, 27 Oct 2017 11:17:51 -0400 (EDT)
Subject: [CentralOH] =?euc-kr?b?MjAxNy0xMC0yNiDUs+3eIFNjcmliYmxlcyDR5t/2?=
 =?euc-kr?b?L+TC2f4/IElkaW9tYXRpYyBMb29wczogaSA8IG4gdmVyc3VzIGkgPD0gbiAt?=
 =?euc-kr?q?_1=3B_json?=
In-Reply-To: <20171027024636.21fc7bd7.jep200404@columbus.rr.com>
References: <20171027024636.21fc7bd7.jep200404@columbus.rr.com>
Message-ID: <alpine.LRH.2.03.1710271114380.29502@bjyevire.pbz>

On Fri, 27 Oct 2017, jep200404 at columbus.rr.com wrote:

> For terminating loops, i < n is the standard idiom, not i <= n - 1.

> See page 12 of "The Practice of Programming" by Kernighan & Pike.

This is probably a caveat from another era -- modern 
language designers noticed this, and a 'forall', or 'foreach' 
construct is present in perl, php, modern C++, and so forth, 
helping 'verifiability' of code by moving to 'all in a set' 
type specification (more mathematical, in the sense  of 'set 
theory')
 
-- Russ herrold

From jep200404 at columbus.rr.com  Fri Oct 27 13:54:47 2017
From: jep200404 at columbus.rr.com (jep200404 at columbus.rr.com)
Date: Fri, 27 Oct 2017 13:54:47 -0400
Subject: [CentralOH] tcl braces versus no braces: what does the manual say
In-Reply-To: <20171020222422.124f124b.jep200404@columbus.rr.com>
References: <20171020222422.124f124b.jep200404@columbus.rr.com>
Message-ID: <20171027135447.191992ee.jep200404@columbus.rr.com>

What does the manual say?

On Fri, 20 Oct 2017 22:24:22 -0400, jep200404 at columbus.rr.com wrote:

> tcl without braces is painfully slow

> tcl with braces is fast

>     doj at sbc:~/20171026$ diff FibForXNoBraces.tcl FibForXWithBraces.tcl
>     12c12
>     <             set Ret_Value [expr $PrevVal + $ThisVal]
>     ---
>     >             set Ret_Value [expr {$PrevVal + $ThisVal}]
>     doj at sbc:~/20171026$ echo 11111 | tclsh FibForXWithBraces.tcl 

The author of that code was perplexed by why the curly braces
made such a huge difference in execution speed.

What does the manual say?

    http://www.tcl.tk/man/tcl8.5/TclCmd/expr.htm#M25

From jmknapp at gmail.com  Fri Oct 27 14:48:34 2017
From: jmknapp at gmail.com (Joe Knapp)
Date: Fri, 27 Oct 2017 14:48:34 -0400
Subject: [CentralOH] Collatz conjecture
Message-ID: <CALwn+dYvvCAwv2SwWeLohX=+WYkKT-+F4bdpktP1jDFgK+bZiw@mail.gmail.com>

In the vein of programming exercises involving sequences (Fibonacci,
Hamming), here's another problem, a mathematical conjecture, that is very
simple to state but at present is classified as unsolved.

Start with any natural number x = 1,2,3,...

For each step:

-- if the number is odd, multiply x by 3 and add 1.
-- if the number is even, divide x by 2
-- stop if x reachs 1, else continue

That's it for constructing the sequence. E.g., starting with x=7:

7 22 11 34 17 52 26 13 40 20 10 5 16 8 4 2 1

The conjecture is that starting from any number will eventually lead to 1.
To date, the conjecture has neither been proved, nor been disproven by
counterexample (a sequence that grows to inifinity, or comes around in a
cycle)..

Legend has it that when this problem first went around university math
departments in the 1960s, work came to a standstill at Yale and the
University of Chicago for a month. Everyone thought that surely they could
resolve this "simple" problem. A joke went around that it was a Soviet plot
to slow mathematical research in the US.

Per wikipedia:

--------------------------
Paul Erd?s said about the Collatz conjecture: "Mathematics may not be ready
for such problems." He also offered $500 for its solution. Jeffrey Lagarias
in 2010 claimed that based only on known information about this problem,
"this is an extraordinarily difficult problem, completely out of reach of
present day mathematics."
--------------------------

Pretty easy to program and explore though. To date, the conjecture has been
verified on massively parallel computers  up to about 10^20. One might say,
well it just has to be true if it's good up to that level, but who knows?

https://en.wikipedia.org/wiki/Collatz_conjecture
https://www.youtube.com/watch?v=K0yMyUn--0s&t=2s

Joe
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