[SciPy-user] (no subject)
James Bednar
jbednar at inf.ed.ac.uk
Wed Oct 3 10:13:52 EDT 2007
Subject: Re: [SciPy-user] plotting a surface
In-Reply-To: <mailman.96104.1191343217.30507.scipy-user at scipy.org>
References: <mailman.96104.1191343217.30507.scipy-user at scipy.org>
X-Mailer: VM 7.18 under Emacs 21.4.1
Reply-To: jbednar at inf.ed.ac.uk
Bcc: jbednar at inf.ed.ac.uk
From: "James A. Bednar" <jbednar at inf.ed.ac.uk>
| Date: Tue, 02 Oct 2007 04:56:56 -0400
| From: Joe Harrington <jh at physics.ucf.edu>
| Subject: Re: [SciPy-user] plotting a surface
| Cc:
| Message-ID: <1191315416.6370.780.camel at glup.physics.ucf.edu>
| Content-Type: text/plain
|
| Or, you could just do it with matplotlib...
|
| http://physicsmajor.wordpress.com/2007/04/22/3d-surface-with-matplotlib/
|
| This was the first hit on a google search for "matplotlib surface". I
| tested it and it works in 0.90.1.
|
| --jh--
|
|
|
|
| ------------------------------
|
| Message: 2
| Date: Tue, 2 Oct 2007 07:42:38 -0400
| From: Tommy Grav <tgrav at mac.com>
| Subject: [SciPy-user] Scipy Superpack for OS X
| To: scipy-user at scipy.org
| Message-ID: <F1E9D29D-D8F0-4B19-B347-2B5E8D7C8DC4 at mac.com>
| Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed
|
| I downloaded the Scipy Superpack for OS X at trichech.us, and noticed
| that there
| are in-consistencies in the different webpages:
|
| scipy.org claims that the binary installation version give you
| version 0.6.0
| trichech.us says that the meta-package contains recent SVN builds of
| version 0.7
| The downloaded scipy superpack for PPC Macintosh however lists the
| version as 0.5.3
| (which is what is installed).
|
| Some reconciliation of the three webpages pointing to the same
| resource might be
| in order.
|
| Cheers
| Tommy
|
|
|
|
| ------------------------------
|
| Message: 3
| Date: Tue, 02 Oct 2007 20:52:38 +0900
| From: David Cournapeau <david at ar.media.kyoto-u.ac.jp>
| Subject: Re: [SciPy-user] Scipy Superpack for OS X
| To: SciPy Users List <scipy-user at scipy.org>
| Message-ID: <47023106.1010901 at ar.media.kyoto-u.ac.jp>
| Content-Type: text/plain; charset=ISO-8859-1; format=flowed
|
| Tommy Grav wrote:
| > I downloaded the Scipy Superpack for OS X at trichech.us, and noticed
| > that there
| > are in-consistencies in the different webpages:
| >
| > scipy.org claims that the binary installation version give you
| > version 0.6.0
| > trichech.us says that the meta-package contains recent SVN builds of
| > version 0.7
| 0.6.0 is released, but 0.7.0 is not yet (SVN build of 0.7 means that it
| is between 0.6 and 0.7, if this is what bothers you here)
| > The downloaded scipy superpack for PPC Macintosh however lists the
| > version as 0.5.3
| > (which is what is installed).
| This looks more like a problem at trichech.us, no ?
|
| cheers,
|
| David
|
|
| ------------------------------
|
| Message: 4
| Date: Tue, 2 Oct 2007 08:21:08 -0400
| From: Tommy Grav <tgrav at mac.com>
| Subject: Re: [SciPy-user] Scipy Superpack for OS X
| To: SciPy Users List <scipy-user at scipy.org>
| Message-ID: <566BB51A-B43D-4E76-ACA9-FD87DFD03F3B at mac.com>
| Content-Type: text/plain; charset=US-ASCII; format=flowed
|
| > This looks more like a problem at trichech.us, no ?
|
| I guess the correct person to correct all this would be
| trichech.us, which is the maintainer of this great resource.
| I just wanted to point out the inconsistencies in the hope
| that someone would be able to reconcile it :)
|
| Cheers
| Tommy
|
|
| ------------------------------
|
| Message: 5
| Date: Tue, 2 Oct 2007 09:37:41 -0400
| From: Alan G Isaac <aisaac at american.edu>
| Subject: Re: [SciPy-user] Hodrick-Prescott filter
| To: SciPy Users List <scipy-user at scipy.org>
| Message-ID: <Mahogany-0.67.0-1576-20071002-093741.00 at american.edu>
| Content-Type: TEXT/PLAIN; CHARSET=UTF-8
|
| On Mon, 1 Oct 2007, Alan G Isaac apparently wrote:
| > I'm looking for a Hodrick-Prescott filter.
| > http://en.wikipedia.org/wiki/Hodrick-Prescott_filter#External_links
| > Is there one in SciPy, or can someone post one?
|
|
| Well, nobody replied to this yet, so here is a really basic
| implementation: ``hpfilter`` in
| http://econpy.googlecode.com/svn/trunk/pytrix/tseries.py
| Suggestions welcome.
|
| Cheers,
| Alan Isaac
|
|
|
|
|
| ------------------------------
|
| Message: 6
| Date: Tue, 2 Oct 2007 08:40:45 -0700
| From: "Christopher Burns" <cburns at berkeley.edu>
| Subject: Re: [SciPy-user] OS X users - Please try multiple
| scipy.test() runs
| To: "SciPy Users List" <scipy-user at scipy.org>
| Message-ID:
| <764e38540710020840j64f0ed1fs5caea77ea0f8a282 at mail.gmail.com>
| Content-Type: text/plain; charset="iso-8859-1"
|
| All tests pass on my OSX machine. Thanks Pearu.
|
| On 10/2/07, Pearu Peterson <pearu at cens.ioc.ee> wrote:
| >
| >
| > I have ported the veclib support from scipy.linalg to
| > scipy.lib.blas. I cannot test it myself. So, anyone
| > on OSX who had problems with scipy.lib, could you
| > execute the following commands:
| >
| > cd svn/scipy/scipy/lib/blas
| > python setup.py build
| > python tests/test_fblas.py
| >
| > to see if tests pass or if there are any compiler errors?
| >
| > Pearu
| >
|
| --
| Christopher Burns, Software Engineer
| Computational Infrastructure for Research Labs
| 10 Giannini Hall, UC Berkeley
| phone: 510.643.4014
| http://cirl.berkeley.edu/
| -------------- next part --------------
| An HTML attachment was scrubbed...
| URL: http://projects.scipy.org/pipermail/scipy-user/attachments/20071002/cab22a10/attachment-0001.html
|
| ------------------------------
|
| Message: 7
| Date: Tue, 2 Oct 2007 09:18:42 -0700
| From: "Dinesh B Vadhia" <dineshbvadhia at hotmail.com>
| Subject: [SciPy-user] NumPy matrix-vector calculation
| To: <scipy-user at scipy.org>
| Message-ID: <BAY109-DAV1B0A9363EF6EB5D46D49DA3AE0 at phx.gbl>
| Content-Type: text/plain; charset="iso-8859-1"
|
| Hello! I am an experienced software engineer but relatively new to Python, NumPy and SciPy. I'll say up front that I've have scanned all the pertinent documentation including the paid-for NumPy book but not found an answer to our problem(s):
|
| We have an MxN (M not equal to N) integer matrix A. The data for A is read-in from a file on persistant storage and the data is immutable (ie. does not change and cannot be changed).
|
| The vector x is a vector of size Nx1. The data elements of x are calculated during the program execution.
|
| We then perform a matrix-vector calculation ie. y = Ax, where the resulting y is a Mx1 vector.
|
| Both x and y are then discarded and a new x and y are calculated and this continues until program execution stops but at all times the matrix A remains the same until ...
|
| Under certain circumstances, we may have to increase the size of M to M+R leaving N alone ie. append R rows to the end of matrix A. We would want to do this while the program is executing.
|
| Here are the questions:
|
| - What NumPy array structure do we use for A - an array or matrix (and why)?
| - If A is a matrix data structure then do the x and y vectors have to be matrix structures too or can you mix the data structures?
| - If A is a matrix or an array structure, can we append rows during program execution and if so, how do we do this?
|
| Any help towards these questions will be gratefully appreciated. Thank-you
|
| Dinesh
| -------------- next part --------------
| An HTML attachment was scrubbed...
| URL: http://projects.scipy.org/pipermail/scipy-user/attachments/20071002/6f1cbb61/attachment-0001.html
|
| ------------------------------
|
| Message: 8
| Date: Tue, 2 Oct 2007 12:39:46 -0400
| From: "Anne Archibald" <peridot.faceted at gmail.com>
| Subject: Re: [SciPy-user] NumPy matrix-vector calculation
| To: "SciPy Users List" <scipy-user at scipy.org>
| Message-ID:
| <ce557a360710020939m7193d209u47202dffd1cdf857 at mail.gmail.com>
| Content-Type: text/plain; charset=UTF-8
|
| On 02/10/2007, Dinesh B Vadhia <dineshbvadhia at hotmail.com> wrote:
|
| > We have an MxN (M not equal to N) integer matrix A. The data for A is
| > read-in from a file on persistant storage and the data is immutable (ie.
| > does not change and cannot be changed).
| >
| > The vector x is a vector of size Nx1. The data elements of x are calculated
| > during the program execution.
| >
| > We then perform a matrix-vector calculation ie. y = Ax, where the resulting
| > y is a Mx1 vector.
| >
| > Both x and y are then discarded and a new x and y are calculated and this
| > continues until program execution stops but at all times the matrix A
| > remains the same until ...
| >
| > Under certain circumstances, we may have to increase the size of M to M+R
| > leaving N alone ie. append R rows to the end of matrix A. We would want to
| > do this while the program is executing.
| >
| > Here are the questions:
| >
| > - What NumPy array structure do we use for A - an array or matrix (and why)?
| > - If A is a matrix data structure then do the x and y vectors have to be
| > matrix structures too or can you mix the data structures?
| > - If A is a matrix or an array structure, can we append rows during program
| > execution and if so, how do we do this?
|
| The only difference between numpy arrays and matrices is the way
| functions act on them - in particular, the * operator behaves
| differently (for arrays it operates elementwise and for matrices it
| applies the matrix product, specifically the function dot()). As data
| structures they are identical.
|
| When you talk about increasing M, that presumably means enlarging A.
| Is your idea that A has changed on disk? (You did say it was
| immutable.) The short answer is that you basically can't enlarge an
| array in place, as it is (under the hood) a single large block of
| memory. Copying is not all that expensive, for a once-in-a-while
| operation, so you can just use hstack() or vstack() or concatenate()
| to enlarge A, allocating a new array in the process. If A is on disk,
| and you want to reflect changes on disk, you can try using numpy's
| memory mapped arrays: these take advantage of your operating system's
| ability to make a disk file look like a piece of memory. Each
| matrix-vector product does require traversing all of A, though, so the
| matrix will need to be loaded into memory regardless. (Incidentally,
| if you combine several vectors into a matrix and multiply them by A
| all at once it will probably be faster, since numpy/scipy uses
| optimized matrix-multiplication routines that are reasonably smart
| about cache.)
|
| Anne
|
|
| ------------------------------
|
| Message: 9
| Date: Tue, 2 Oct 2007 18:40:13 +0200
| From: "Matthieu Brucher" <matthieu.brucher at gmail.com>
| Subject: Re: [SciPy-user] NumPy matrix-vector calculation
| To: "SciPy Users List" <scipy-user at scipy.org>
| Message-ID:
| <e76aa17f0710020940y1e752f8cy8d34de10aecdb54a at mail.gmail.com>
| Content-Type: text/plain; charset="iso-8859-1"
|
| Hi,
|
| Matrix and array are basically the same, you can do what you want with both,
| the only difference you will notice is that the multplication is the matrix
| multiplication in one case and the elementwise multiplication in the other
| case. Just try to be consistent and use only matrix or only arrays.
| Then, if you have to add rows or columns, see hstack() and vstack()
|
| Matthieu
|
| 2007/10/2, Dinesh B Vadhia <dineshbvadhia at hotmail.com>:
| >
| > Hello! I am an experienced software engineer but relatively new to
| > Python, NumPy and SciPy. I'll say up front that I've have scanned all the
| > pertinent documentation including the paid-for NumPy book but not found an
| > answer to our problem(s):
| >
| > We have an MxN (M not equal to N) integer matrix A. The data for A is
| > read-in from a file on persistant storage and the data is immutable (ie.
| > does not change and cannot be changed).
| >
| > The vector x is a vector of size Nx1. The data elements of x are
| > calculated during the program execution.
| >
| > We then perform a matrix-vector calculation ie. y = Ax, where the
| > resulting y is a Mx1 vector.
| >
| > Both x and y are then discarded and a new x and y are calculated and this
| > continues until program execution stops but at all times the matrix A
| > remains the same until ...
| >
| > Under certain circumstances, we may have to increase the size of M to M+R
| > leaving N alone ie. append R rows to the end of matrix A. We would want to
| > do this while the program is executing.
| >
| > Here are the questions:
| >
| > - What NumPy array structure do we use for A - an array or matrix (and
| > why)?
| > - If A is a matrix data structure then do the x and y vectors have to be
| > matrix structures too or can you mix the data structures?
| > - If A is a matrix or an array structure, can we append rows during
| > program execution and if so, how do we do this?
| >
| > Any help towards these questions will be gratefully appreciated.
| > Thank-you
| >
| > Dinesh
| >
| >
| > _______________________________________________
| > SciPy-user mailing list
| > SciPy-user at scipy.org
| > http://projects.scipy.org/mailman/listinfo/scipy-user
| >
| >
| -------------- next part --------------
| An HTML attachment was scrubbed...
| URL: http://projects.scipy.org/pipermail/scipy-user/attachments/20071002/d1fcd0e8/attachment.html
|
| ------------------------------
|
| _______________________________________________
| SciPy-user mailing list
| SciPy-user at scipy.org
| http://projects.scipy.org/mailman/listinfo/scipy-user
|
|
| End of SciPy-user Digest, Vol 50, Issue 3
| *****************************************
More information about the SciPy-User
mailing list