Re: [Numpy-discussion] loadtxt issues

2009-02-10 Thread Brent Pedersen
On Tue, Feb 10, 2009 at 9:40 PM, A B wrote: > Hi, > > How do I write a loadtxt command to read in the following file and > store each data point as the appropriate data type: > > 12|h|34.5|44.5 > 14552|bbb|34.5|42.5 > > Do the strings have to be read in separately from the numbers? > > Why would a

[Numpy-discussion] loadtxt issues

2009-02-10 Thread A B
Hi, How do I write a loadtxt command to read in the following file and store each data point as the appropriate data type: 12|h|34.5|44.5 14552|bbb|34.5|42.5 Do the strings have to be read in separately from the numbers? Why would anyone use 'S10' instead of 'string'? dt = {'names': ('gender',

Re: [Numpy-discussion] Permutations in Simulations`

2009-02-10 Thread Mark Janikas
You are correct! Thanks to all! MJ -Original Message- From: numpy-discussion-boun...@scipy.org [mailto:numpy-discussion-boun...@scipy.org] On Behalf Of Keith Goodman Sent: Tuesday, February 10, 2009 6:07 PM To: Discussion of Numerical Python Subject: Re: [Numpy-discussion] Permutations

Re: [Numpy-discussion] Permutations in Simulations`

2009-02-10 Thread Keith Goodman
Yeah, good point. The second argsort isn't needed. That should speed things up. The double argsort ranks the values in the array. But we don't need that here. On Tue, Feb 10, 2009 at 5:31 PM, wrote: > very nice. What's the purpose of the second `.argsort(0)` ? Doesn't > it also work without it

Re: [Numpy-discussion] Permutations in Simulations`

2009-02-10 Thread josef . pktd
very nice. What's the purpose of the second `.argsort(0)` ? Doesn't it also work without it, or am I missing something in how this works?> Josef On 2/10/09, Mark Janikas wrote: > Thanks to all for your replies. I want this to work on any vector so I was > thinking this...? > > import numpy as

Re: [Numpy-discussion] Permutations in Simulations`

2009-02-10 Thread Mark Janikas
Thanks to all for your replies. I want this to work on any vector so I was thinking this...? import numpy as np import timeit x = np.array([4.,5.,10.,3.,5.,6.,7.,2.,9.,1.]) nx = 10 ny = 100 def weirdshuffle4(x, ny): nx = len(x) indices = np.random.random_sample((nx,ny)).argsort(0).argso

Re: [Numpy-discussion] Permutations in Simulations`

2009-02-10 Thread Mark Miller
Got it. Thanks! On Tue, Feb 10, 2009 at 1:50 PM, Keith Goodman wrote: > On Tue, Feb 10, 2009 at 1:41 PM, Mark Miller > wrote: >> Out of curiosity, why wouldn't numpy.apply_along_axis be a reasonable >> approach here. Even more curious: why is it slower than the original >> explicit loop? > >

Re: [Numpy-discussion] Permutations in Simulations`

2009-02-10 Thread Keith Goodman
On Tue, Feb 10, 2009 at 1:41 PM, Mark Miller wrote: > Out of curiosity, why wouldn't numpy.apply_along_axis be a reasonable > approach here. Even more curious: why is it slower than the original > explicit loop? I took a quick look at the apply_along_axis code. It is numpy code (not c) and it u

Re: [Numpy-discussion] Permutations in Simulations`

2009-02-10 Thread Mark Miller
Out of curiosity, why wouldn't numpy.apply_along_axis be a reasonable approach here. Even more curious: why is it slower than the original explicit loop? Learning, -Mark import numpy as np import timeit def baseshuffle(nx, ny): x = np.arange(nx) res = np.zeros((nx,ny),int) for sim

Re: [Numpy-discussion] numpy-izing a loop

2009-02-10 Thread Stéfan van der Walt
2009/2/10 Stéfan van der Walt : > x = np.arange(dim) > y = np.arange(dim)[:, None] > z = np.arange(dim)[:, None, None] Do not operate heavy machinery or attempt broadcasting while tired or under the influence. That order was incorrect: > z = np.arange(dim) > y = np.arange(dim)[:, None] > x = np.

Re: [Numpy-discussion] numpy-izing a loop

2009-02-10 Thread Stéfan van der Walt
2009/2/10 Robert Kern : > x = np.arange(dim)[:,np.newaxis,np.newaxis] > y = np.arange(dim)[np.newaxis,:,np.newaxis] > z = np.arange(dim)[np.newaxis,np.newaxis,:] Yes, sorry, I should have copied from my terminal. I think I had x = np.arange(dim) y = np.arange(dim)[:, None] z = np.arange(dim)[

Re: [Numpy-discussion] from_function

2009-02-10 Thread Yakov Keselman
Perhaps you can do something along the following lines to get around this limitation: # # parameterizes the original function by delta, size. def parameterized_function(delta, size, function): center = (size-1)/2.0 return lambda i: function( (i-center)*delta ) # the func

Re: [Numpy-discussion] Permutations in Simulations`

2009-02-10 Thread Keith Goodman
On Tue, Feb 10, 2009 at 12:41 PM, Keith Goodman wrote: > On Tue, Feb 10, 2009 at 12:28 PM, Keith Goodman wrote: >> On Tue, Feb 10, 2009 at 12:18 PM, Keith Goodman wrote: >>> On Tue, Feb 10, 2009 at 11:29 AM, Mark Janikas wrote: I want to create an array that contains a column of permutatio

Re: [Numpy-discussion] Permutations in Simulations`

2009-02-10 Thread Keith Goodman
On Tue, Feb 10, 2009 at 12:28 PM, Keith Goodman wrote: > On Tue, Feb 10, 2009 at 12:18 PM, Keith Goodman wrote: >> On Tue, Feb 10, 2009 at 11:29 AM, Mark Janikas wrote: >>> I want to create an array that contains a column of permutations for each >>> simulation: >>> >>> import numpy as NUM >>> >

Re: [Numpy-discussion] Permutations in Simulations`

2009-02-10 Thread Keith Goodman
On Tue, Feb 10, 2009 at 12:18 PM, Keith Goodman wrote: > On Tue, Feb 10, 2009 at 11:29 AM, Mark Janikas wrote: >> I want to create an array that contains a column of permutations for each >> simulation: >> >> import numpy as NUM >> >> import numpy.random as RAND >> >> x = NUM.arange(4.) >> >> res

Re: [Numpy-discussion] Permutations in Simulations`

2009-02-10 Thread Keith Goodman
On Tue, Feb 10, 2009 at 11:29 AM, Mark Janikas wrote: > I want to create an array that contains a column of permutations for each > simulation: > > import numpy as NUM > > import numpy.random as RAND > > x = NUM.arange(4.) > > res = NUM.zeros((4,100)) > > > for sim in range(100): > > res[:,sim] =

Re: [Numpy-discussion] numpy-izing a loop

2009-02-10 Thread Robert Kern
On Tue, Feb 10, 2009 at 10:19, Stéfan van der Walt wrote: > Hi Paul > > 2009/2/10 Paul Rudin : >> >> I've just written this snippet of code: >> >> result = numpy.empty((dim, dim, dim), numpy.bool) >> for x in xrange(dim): >>for y in xrange(dim): >>for z in xrange(dim): >>re

[Numpy-discussion] Permutations in Simulations`

2009-02-10 Thread Mark Janikas
Hello All, I want to create an array that contains a column of permutations for each simulation: import numpy as NUM import numpy.random as RAND x = NUM.arange(4.) res = NUM.zeros((4,100)) for sim in range(100): res[:,sim] = RAND.permutation(x) Is there a way to do this without a loop? Thank

Re: [Numpy-discussion] numpy-izing a loop

2009-02-10 Thread Stéfan van der Walt
Hi Paul 2009/2/10 Paul Rudin : > > I've just written this snippet of code: > > result = numpy.empty((dim, dim, dim), numpy.bool) > for x in xrange(dim): >for y in xrange(dim): >for z in xrange(dim): >result[x, y, z] = ((xnear[y, z] < xfar[y, z]) and >

[Numpy-discussion] Unnecessary axes in recarrays

2009-02-10 Thread Ravi
Hi, Recarrays seem to sprout extra axes when they are nested: In [98]: np.__version__ Out[98]: '1.2.0' In [99]: d1 = dtype( [ ('a',uint8,2), ('b',uint8,1) ] ) In [100]: d2 = dtype( [ ('c',uint8,1), ('d',d1,1) ] ) In [101]: d3 = dtype( [ ('c',uint8,1), ('d',d1,2) ] ) In [102]: a1 = zeros

Re: [Numpy-discussion] linalg.norm missing an 'axis' kwarg?!

2009-02-10 Thread Stéfan van der Walt
Hi Hans 2009/2/10 Hans Meine : > If you look at the patch I posted (OK, that was some weeks ago, so I'll attach > it again for your convenience), that's (more or less) exactly what I proposed. Would you mind adding some tests to the patch? Cheers Stéfan __

[Numpy-discussion] Solaris 8, 32 bit python issue

2009-02-10 Thread Christopher Hanley
This problem is on a 32bit Solaris 8 system. == FAIL: Test find_duplicates -- Traceback (most recent call last): File "/usr/ra/pyssg/2.5.1/numpy/lib/tests/test

Re: [Numpy-discussion] linalg.norm missing an 'axis' kwarg?!

2009-02-10 Thread Hans Meine
On Tuesday 10 February 2009 11:11:38 Markus Rosenstihl wrote: > i usually do something like this: > > a = random.rand(3000) > a.resize((1000,3)) > vec_norms = sqrt(sum(a**2,axis=1)) If you look at the patch I posted (OK, that was some weeks ago, so I'll attach it again for your convenience), that

[Numpy-discussion] numpy-izing a loop

2009-02-10 Thread Paul Rudin
I've just written this snippet of code: result = numpy.empty((dim, dim, dim), numpy.bool) for x in xrange(dim): for y in xrange(dim): for z in xrange(dim): result[x, y, z] = ((xnear[y, z] < xfar[y, z]) and (ynear[x, z] < yfar[x, z]) and

Re: [Numpy-discussion] porting NumPy to Python 3

2009-02-10 Thread Scott Sinclair
> 2009/2/10 James Watson : > I want to make sure diffs are against latest code, but keep getting > this svn error: > svn update > svn: OPTIONS of 'http://scipy.org/svn/numpy/trunk': Could not read > status line: Connection reset by peer (http://scipy.org) There is some problem at the moment. This

Re: [Numpy-discussion] porting NumPy to Python 3

2009-02-10 Thread James Watson
I'm taking Chuck and Bruce's suggestions and making sure that the changes are compatible with Python 2.4 and 2.6. I want to make sure diffs are against latest code, but keep getting this svn error: svn update svn: OPTIONS of 'http://scipy.org/svn/numpy/trunk': Could not read status line: Connectio

Re: [Numpy-discussion] ANN: HDF5 for Python 1.1

2009-02-10 Thread Francesc Alted
Hi Stephen, A Tuesday 10 February 2009, Stephen Simmons escrigué: > I have lots of LZO-compressed datasets created with PyTables. > There's a real barrier to using both h5py and PyTables if the fast > decompressor options are just LZF on h5py and LZO on PyTables. You can always use ptrepack utili

Re: [Numpy-discussion] linalg.norm missing an 'axis' kwarg?!

2009-02-10 Thread Markus Rosenstihl
Am 20.11.2008 um 11:11 schrieb Hans Meine: > Hi, > > I have a 2D matrix comprising a sequence of vectors, and I want to > compute the > norm of each vector. np.linalg.norm seems to be the best bet, but > it does not > support axis. Wouldn't this be a nice feature? Hi, i usually do somethi

Re: [Numpy-discussion] ANN: HDF5 for Python 1.1

2009-02-10 Thread Francesc Alted
A Monday 09 February 2009, Ondrej Certik escrigué: > On Mon, Feb 9, 2009 at 12:15 PM, Andrew Collette wrote: > > = > > Announcing HDF5 for Python (h5py) 1.1 > > = > > > > What is h5py? > > - > > > > HDF5 for Pytho

Re: [Numpy-discussion] ANN: HDF5 for Python 1.1

2009-02-10 Thread Andrew Collette
Hi Stephen, There are no immediate plans to support LZO in h5py, and in fact I'm starting to regret including any fast compressor at all as I'm now responsible for maintaining it. :) The reason for the dichotomy is that LZO is released under the GPL, which is incompatible with h5py's license. The