Re: [Numpy-discussion] Newbee question - looking to use Numpy to solve permutation problem

2007-01-27 Thread Robert Kern
Chris Toczycki wrote: > I am looking to find a solution to a problem and believe that Numpy may > help. I'd appreciate some advice and/or direction and I'll pursue from > there. > > The problem is that I am looking for a most efficient solution where I > have to select 25 solutions where the high

[Numpy-discussion] ATTN: Developers - Pyrex 0.9.5 is out

2007-01-27 Thread Robert Kern
I made a few minor adjustments to make sure that Pyrex 0.9.5 builds mtrand.pyx cleanly. It's a bit pickier than previous versions. However, it also generates C code that compiles without warnings! Consequently, I recommend that all numpy developers should upgrade to Pyrex 0.9.5 and cease using the

[Numpy-discussion] Newbee question - looking to use Numpy to solve permutation problem

2007-01-27 Thread Chris Toczycki
I am looking to find a solution to a problem and believe that Numpy may help. I'd appreciate some advice and/or direction and I'll pursue from there. The problem is that I am looking for a most efficient solution where I have to select 25 solutions where the highest pair-covariance value is th

Re: [Numpy-discussion] kron bug with zero-length dimensions?

2007-01-27 Thread Bill Baxter
Theres also numpy.tile which is like a repmat generalized to N-dim. --bb On 1/27/07, Sven Schreiber <[EMAIL PROTECTED]> wrote: > Sven Schreiber schrieb: > > Hi, > > > > the kron(a,b) function seems to allow shapes such as (0,x) or (y,0) only > > for the second argument b, not for the first argumen

Re: [Numpy-discussion] Different results from repeated calculation

2007-01-27 Thread Keith Goodman
On 1/27/07, Fernando Perez <[EMAIL PROTECTED]> wrote: > It's definitely looking like something SMP related: on my laptop, with > everything other than the hardware being identical (Linux distro, > kernel, numpy build, etc), I can't make it fail no matter how I muck > with it. I always get '0 diffe

Re: [Numpy-discussion] Different results from repeated calculation

2007-01-27 Thread Fernando Perez
On 1/27/07, Robert Kern <[EMAIL PROTECTED]> wrote: > Fernando Perez wrote: > > > That's it. One comment char removed, and something that's done > > /after/ the tests are actually executed. > > > > That kind of 'I add a printf() call and the bug disappears' is > > unpleasantly reminiscent of lurkin

Re: [Numpy-discussion] Different results from repeated calculation

2007-01-27 Thread Robert Kern
Fernando Perez wrote: > That's it. One comment char removed, and something that's done > /after/ the tests are actually executed. > > That kind of 'I add a printf() call and the bug disappears' is > unpleasantly reminiscent of lurking pointer errors in C code... Heh. Fantastic. It might be wort

Re: [Numpy-discussion] Different results from repeated calculation

2007-01-27 Thread Stefan van der Walt
On Sat, Jan 27, 2007 at 03:11:58PM -0700, Charles R Harris wrote: > So this looks like an error in the LSB of the floating number. Could be > rounding, could be something not reset quite right. I'm thinking possibly > hardware at this time, maybe compiler. > > Linux fedora 2.6.19-1.2895.fc6 #1 SMP

Re: [Numpy-discussion] Different results from repeated calculation

2007-01-27 Thread Stefan van der Walt
On Sat, Jan 27, 2007 at 04:11:59PM -0700, Fernando Perez wrote: > OK, this is weird. I modified the repeat code a little to ease > collecting of results, and all of a sudden the differences went away. > If you look at the attached code, here's what happens for me: > > a) If I have line 77 like th

Re: [Numpy-discussion] Different results from repeated calculation

2007-01-27 Thread Robert Kern
Charles R Harris wrote: > Hmmm, and your problem machine is running smp linux. As is mine; fedora > uses smp even on single processor machines these days. I think we could > use more data here comparing > > OSX [today]$ python repeat.py ---

Re: [Numpy-discussion] Different results from repeated calculation

2007-01-27 Thread Charles R Harris
On 1/27/07, Fernando Perez <[EMAIL PROTECTED]> wrote: On 1/27/07, Fernando Perez <[EMAIL PROTECTED]> wrote: > On 1/27/07, Charles R Harris <[EMAIL PROTECTED]> wrote: > > > Hmmm, and your problem machine is running smp linux. As is mine; fedora uses > > smp even on single processor machines these

Re: [Numpy-discussion] Different results from repeated calculation

2007-01-27 Thread Stefan van der Walt
On Sat, Jan 27, 2007 at 04:00:33PM -0700, Charles R Harris wrote: > Hmmm, and your problem machine is running smp linux. As is mine; fedora uses > smp even on single processor machines these days. I think we could use more > data here comparing It runs fine on this Ubuntu/Edgy machine, though: Li

Re: [Numpy-discussion] Different results from repeated calculation

2007-01-27 Thread Fernando Perez
On 1/27/07, Fernando Perez <[EMAIL PROTECTED]> wrote: > On 1/27/07, Charles R Harris <[EMAIL PROTECTED]> wrote: > > > Hmmm, and your problem machine is running smp linux. As is mine; fedora uses > > smp even on single processor machines these days. I think we could use more > > data here comparing

Re: [Numpy-discussion] Different results from repeated calculation

2007-01-27 Thread Fernando Perez
On 1/27/07, Charles R Harris <[EMAIL PROTECTED]> wrote: Hmmm, and your problem machine is running smp linux. As is mine; fedora uses smp even on single processor machines these days. I think we could use more data here comparing OSX Linux (single, smp) Window OK, this is weird. I modified th

Re: [Numpy-discussion] Different results from repeated calculation

2007-01-27 Thread Charles R Harris
On 1/27/07, Stefan van der Walt <[EMAIL PROTECTED]> wrote: On Sat, Jan 27, 2007 at 03:11:58PM -0700, Charles R Harris wrote: > Does anyone else see this happening? > > > Yes, > > test1: 0 differences > test2: 51 differences > test3: 0 differences > > Oddly, the relative error is alway

Re: [Numpy-discussion] kron bug with zero-length dimensions?

2007-01-27 Thread Sven Schreiber
Sven Schreiber schrieb: > Hi, > > the kron(a,b) function seems to allow shapes such as (0,x) or (y,0) only > for the second argument b, not for the first argument a. (See below for > examples.) > > Maybe it's too harsh to call it a bug because the result is typically > not defined mathematically.

Re: [Numpy-discussion] Different results from repeated calculation

2007-01-27 Thread Stefan van der Walt
On Sat, Jan 27, 2007 at 03:11:58PM -0700, Charles R Harris wrote: > Does anyone else see this happening? > > > Yes, > > test1: 0 differences > test2: 51 differences > test3: 0 differences > > Oddly, the relative error is always the same: > > 98 z different 2.0494565872e-16 > 99 z di

Re: [Numpy-discussion] python's random.random() faster than numpy.random.rand() ???

2007-01-27 Thread Stefan van der Walt
Hi Mark On Fri, Jan 26, 2007 at 10:17:58AM -0700, Mark P. Miller wrote: > I've recently been working with numpy's random number generators and > noticed that python's core random number generator is faster than > numpy's for the uniform distribution. > > In other words, > > for a in range(1000

Re: [Numpy-discussion] Different results from repeated calculation

2007-01-27 Thread Charles R Harris
On 1/27/07, Stefan <[EMAIL PROTECTED]> wrote: I can't reproduce this under Linux, r3510. Output is test1: 0 differences test2: 0 differences test3: 0 differences Does anyone else see this happening? Yes, test1: 0 differences test2: 51 differences test3: 0 differences Oddly, t

Re: [Numpy-discussion] python's random.random() faster than numpy.random.rand() ???

2007-01-27 Thread Robert Kern
Mark P. Miller wrote: > Greetings: > > I've recently been working with numpy's random number generators and > noticed that python's core random number generator is faster than > numpy's for the uniform distribution. > > In other words, > > for a in range(100): > b = random.random()

Re: [Numpy-discussion] added 1.0.1 release notes to wiki

2007-01-27 Thread Sven Schreiber
Martin Spacek schrieb: > Just a note that I've copied over the 1.0.1 release notes from SourceForge: > > http://sourceforge.net/project/shownotes.php?group_id=1369&release_id=468153 > > over to the wiki: > > http://scipy.org/ReleaseNotes/NumPy_1.0 Thank you! > > Should 1.0.1 get its own page,

Re: [Numpy-discussion] python's random.random() faster than numpy.random.rand() ???

2007-01-27 Thread Simon Burton
On Fri, 26 Jan 2007 10:17:58 -0700 "Mark P. Miller" <[EMAIL PROTECTED]> wrote: > > for a in range(100): > b = numpy.random.rand()#numpy code what about numpy.random.rand(100) ? Simon. ___ Numpy-discussion mailing list Numpy-discussion

[Numpy-discussion] python's random.random() faster than numpy.random.rand() ???

2007-01-27 Thread Mark P. Miller
Greetings: I've recently been working with numpy's random number generators and noticed that python's core random number generator is faster than numpy's for the uniform distribution. In other words, for a in range(100): b = random.random()#core python code is substantially faste

Re: [Numpy-discussion] Different results from repeated calculation

2007-01-27 Thread Stefan
I can't reproduce this under Linux, r3510. Output is test1: 0 differences test2: 0 differences test3: 0 differences Does anyone else see this happening? Regards Stéfan On Sat, Jan 27, 2007 at 12:25:18PM -0800, Keith Goodman wrote: > I get slightly different results when I repeat a calcul

[Numpy-discussion] Different results from repeated calculation

2007-01-27 Thread Keith Goodman
I get slightly different results when I repeat a calculation. In a long simulation the differences snowball and swamp the effects I am trying to measure. In the attach script there are three tests. In test1, I construct matrices x and y and then repeatedly calculate z = calc(x,y). The result z i