[FAQTS] Python Knowledge Base Update -- July 10th, 2000

[Fiona Czuczman]

Hi Guys,

Below are the latest entries to be entered into http://python.faqts.com

cheers,

Fiona Czuczman


## New Entries #################################################


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How can I do this Perl paragraph mode in Python? $/ = '';  # paragraph mode
http://www.faqts.com/knowledge-base/view.phtml/aid/4629
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Fiona Czuczman
Harry George

If you use pyperl:
p=pyperl.Pyperl()
p.INPUT_RECORD_SEPARATOR=''
myfile=p.open("< $filename")
lines=myfile.readlines()


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Is there anywhere I can get a list of the commands for python?
http://www.faqts.com/knowledge-base/view.phtml/aid/4630
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Fiona Czuczman
Peter Schneider-Kamp

Try the library and the language reference at http://www.python.org/doc


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How can I ring the PC's bell (ie internal speaker) to alert the operator that an operation has finished running?
http://www.faqts.com/knowledge-base/view.phtml/aid/4632
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Fiona Czuczman
David Porter

print "\a"


## Edited Entries ##############################################


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Is there a command/function in python to put a delay or wait step into a program?
Does python have a sleep function? e.g. sleep(60) to wait 60 seconds?
http://www.faqts.com/knowledge-base/view.phtml/aid/2609
-------------------------------------------------------------
Nathan Wallace, Fiona Czuczman
Andreas Jung,Greg Fortune, pehr anderson

Try the sleep function in the time module.

  import time
  time.sleep(60)

And put this in a while loop and a statement will only execute on the
minute...  That allows you to run a statement at predefined intervals
regardless of how long the command takes (as long as it takes less than 
a minute or 5 or 60 or whatever you set it to)  For example, I wanted to 
run a ping once a minute.  If I just time.sleep(60) or time.sleep(45) 
even, the ping will not always take the same amount of time.  Here's the 
code :)

time.sleep(time.localtime(time.time())[5])
The [5] just pulls the seconds out of the time.localtime()'s return 
value.

The great thing about time.sleep is that it supports floating point 
numbers!

import time
time.sleep(0.1) 

http://python.org/doc/current/lib/module-time.html


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Why are there no operators equivalent to C's   , --,  =, etc.?
http://www.faqts.com/knowledge-base/view.phtml/aid/3378
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Fiona Czuczman
Fredrik Lundh, Peter Schneider-Kamp, Michael Hudson

if you write things like "var = var + 1" a lot, you might be missing 
some important python idioms...

here are a few, in no specific order:

    for item in sequence:
        ...

    sequence = map(operation, sequence)

    sequence.append(item)

    for index in range(size):
        ...

    for item1, item2 in map(None, sequence1, sequence):
        ...

    for index in range(start, stop, step):
        ...

    n = sequence.count(item)

    for index in range(len(sequence)):
        ...

    sequence.remove(item)

    for index in range(len(sequence)-1, -1, -1):
        ...

(also note that most basic types are *immutable*, so it's not entirely 
clear how things like ++ and += should work.

Michael Hudson wrote a patch for the +=, -=, *=, /= and some other
of these operators.

A patch can be found at:

http://starship.python.net/crew/mwh/aug-patch.html
http://www-jcsu.jesus.cam.ac.uk/~mwh21/aug-patch.html


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What is the best way of setting default options of widgets?
http://www.faqts.com/knowledge-base/view.phtml/aid/4151
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Fiona Czuczman
richard_chamberlain,Cameron Laird

You can use an option database. If you create a file called optionDB 
with for example the following kind of entries:

*font:                   Times New Roman
*Button*foreground       blue
*foreground              black

You can then apply these via

root.option_readfile('optionDB')

For more on this, see

http://www.regularexpressions.com/#options


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Is there a utility to convert module docstrings to HTML for nice documentation?
http://www.faqts.com/knowledge-base/view.phtml/aid/4610
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Stu D, Fiona Czuczman
Richard Jones

>From http://starship.python.net/crew/danilo/download.html:

Gendoc generates documentation from Python source code in different 
formats. Currently it can generate HTML, MIF, MML and plain old ascii 
(MIF and MML are FrameMaker formats). If you want to generate HTML 
files, I strongly suggest you grab a copy of Robin Friedrich's HTMLgen 
package, with which gendoc generates quite nice pages, optionally with 
frames.