Re: [Numpy-discussion] Is numpy.convolve based on LAPACK routine?

2010-11-11 Thread braingateway
Pauli Virtanen : > On Thu, 11 Nov 2010 00:43:32 +0100, LittleBigBrain wrote: > >> I am wondering, is numpy.convolve based on LAPACK routine? Can it be >> speedup by using ATLAS? >> > > LAPACK and Atlas do not AFAIK have convolution routines -- that's not > linear algebra. MKL on the other

Re: [Numpy-discussion] LapackError:non-native byte order

2010-11-08 Thread braingateway
Matthew Brett : > Hi, > > On Mon, Nov 8, 2010 at 10:34 AM, Pauli Virtanen wrote: > >> Mon, 08 Nov 2010 19:31:31 +0100, Pauli Virtanen wrote: >> >> >>> ma, 2010-11-08 kello 18:56 +0100, LittleBigBrain kirjoitti: >>> In my system '<' is the native byte-order, but unless I change

[Numpy-discussion] scipy.linalg.solve()'s overwrite option does not work

2010-11-05 Thread braingateway
Hi everyone, I believe the overwrite option is used for reduce memory usage. But I did following test, and find out it does not work at all. Maybe I misunderstood the purpose of overwrite option. If anybody could explain this, I shall highly appreciate your help. >>> a=npy.random.randn(20,20) >>>

[Numpy-discussion] flattened index for Sparse Matrix?

2010-11-04 Thread braingateway
Hi Everyone, I am trying sparse matrix these days. I am wondering is there any way I can access the sparse matrix with flattened index? For example: a=numpy.matrix([[0,1,2],[3,4,5]) matrix([[0, 1, 2], [3, 4, 5]]) >>> >>>print a.flat[3] >>> 3 >>> >>> a.flat[3]=10 >>> >>> print a >>

Re: [Numpy-discussion] strange behavior of ravel() and flatnonzero() on matrix

2010-11-03 Thread braingateway
braingateway : >>>> aa=matrix([[-1, 2, 0],[0, 0, 3]]) >>>> aa >>>> > matrix([[-1, 2, 0], > [ 0, 0, 3]]) > >>>> aa.nonzero() >>>> > (matrix([[0, 0, 1]], dtype=int64), matrix([[0, 1, 2]], dtype=int64)) >

[Numpy-discussion] strange behavior of ravel() and flatnonzero() on matrix

2010-11-03 Thread braingateway
>>> aa=matrix([[-1, 2, 0],[0, 0, 3]]) >>> aa matrix([[-1, 2, 0], [ 0, 0, 3]]) >>> aa.nonzero() (matrix([[0, 0, 1]], dtype=int64), matrix([[0, 1, 2]], dtype=int64)) *OK* >>> npy.nonzero(aa.flat) (array([0, 1, 5], dtype=int64),) *OK* >>> flatnonzero(aa) matrix([[0, 0,

Re: [Numpy-discussion] large float32 array issue

2010-11-03 Thread braingateway
Vincent Schut : > Hi, I'm running in this strange issue when using some pretty large > float32 arrays. In the following code I create a large array filled with > ones, and calculate mean and sum, first with a float64 version, then > with a float32 version. Note the difference between the two. NB

Re: [Numpy-discussion] How to limit the numpy.memmap's RAM usage?

2010-10-23 Thread braingateway
Charles R Harris On Sat, Oct 23, 2010 at 10:27 AM, braingateway <mailto:braingate...@gmail.com>> wrote: Charles R Harris : > > > On Sat, Oct 23, 2010 at 10:15 AM, Charles R Harris > mailto:charlesr.har...@gmail.com> <mailt

Re: [Numpy-discussion] How to limit the numpy.memmap's RAM usage?

2010-10-23 Thread braingateway
Charles R Harris : > > > On Sat, Oct 23, 2010 at 10:15 AM, Charles R Harris > mailto:charlesr.har...@gmail.com>> wrote: > > > > On Sat, Oct 23, 2010 at 9:44 AM, braingateway > mailto:braingate...@gmail.com>> wrote: > > David Cournap

Re: [Numpy-discussion] How to limit the numpy.memmap's RAM usage?

2010-10-23 Thread braingateway
David Cournapeau : 2010/10/23 braingateway : Hi everyone, I noticed the numpy.memmap using RAM to buffer data from memmap files. If I get a 100GB array in a memmap file and process it block by block, the RAM usage is going to increasing with the process running until there is no available

[Numpy-discussion] How to limit the numpy.memmap's RAM usage?

2010-10-23 Thread braingateway
Hi everyone, I noticed the numpy.memmap using RAM to buffer data from memmap files. If I get a 100GB array in a memmap file and process it block by block, the RAM usage is going to increasing with the process running until there is no available space in RAM (4GB), even though the block size is only

Re: [Numpy-discussion] Is there anyway to read raw binary file via pytable?

2010-07-29 Thread BrainGateway
2010/7/28 Ken Watford : > 2010/7/28 脑关生命科学仪器 : >> it seems like pytable only support HDF5. I had some 500GB numerical arrays >> to process. Pytable claims to have some advance feature to enhance >> processing speed and largely reduce physical memory requirement. However, I >> do not wanna touch the

[Numpy-discussion] Is there anyway to read raw binary file via pytable?

2010-07-28 Thread BrainGateway
it seems like pytable only support HDF5. I had some 500GB numerical arrays to process. Pytable claims to have some advance feature to enhance processing speed and largely reduce physical memory requirement. However, I do not wanna touch the raw data I had. Simply because I do not have doubled disks