On Tue, Jan 12, 2010 at 4:11 PM, Jankins wrote:
Hi
On my Ubuntu, I would reach the arpack wrapper as follows:
from scipy.sparse.linalg.eigen.arpack import eigen
However, I'd guess that you deal with a symmetric matrix (Laplacian or
adjacency matrix), so the symmetric solver might be the best c
On Sat, Sep 27, 2008 at 2:36 AM, Robert Kern <[EMAIL PROTECTED]> wrote:
> On Wed, Sep 17, 2008 at 07:12, Arnar Flatberg <[EMAIL PROTECTED]>
> wrote:
> >
> > On Wed, Sep 17, 2008 at 3:56 AM, Robert Kern <[EMAIL PROTECTED]>
> wrote:
>
> There is now
On Sun, Sep 21, 2008 at 7:51 PM, Dinesh B Vadhia
<[EMAIL PROTECTED]>wrote:
> Ooops, I should have said that this is easy to do with 2 for loops ie.
>
> import numpy
> from collections import defaultdict
> A =
> [[1 6 1 2 3]
> [4 5 4 7 0]
> [2 0 8 0 2]
> [0 0 0 3 7]
> [0 7 0 3 5]
> [8 0 3 0 6
On Fri, Sep 19, 2008 at 4:09 PM, lorenzo <[EMAIL PROTECTED]> wrote:
>
>
> On Fri, Sep 19, 2008 at 2:50 PM, Arnar Flatberg <[EMAIL PROTECTED]>wrote:
>
>>
>>
>> I think
>> [x*y for x in a for y in b]
>> feels pythonic, however it has a surpri
On Fri, Sep 19, 2008 at 3:09 PM, Stéfan van der Walt <[EMAIL PROTECTED]>wrote:
> 2008/9/19 mark <[EMAIL PROTECTED]>:
> > I need to multiply items in a list and need a list back. Which one of
> > the four options is best (I thought in Python there was only one way
> > to do something???)
>
> With t
On Wed, Sep 17, 2008 at 10:33 PM, Robert Kern <[EMAIL PROTECTED]> wrote:
> On Wed, Sep 17, 2008 at 07:12, Arnar Flatberg <[EMAIL PROTECTED]>
> wrote:
> >
> > On Wed, Sep 17, 2008 at 3:56 AM, Robert Kern <[EMAIL PROTECTED]>
> wrote:
>
> It should be s
On Wed, Sep 17, 2008 at 3:56 AM, Robert Kern <[EMAIL PROTECTED]> wrote:
>
> So, I could use some comments on the workflow. Does this look sensible
> to everyone? How else would you like to use it?
>
Works for me. I would love to use it as a part of an ipython session.
Initially, I sprinkled som $
On Mon, Sep 15, 2008 at 5:18 PM, Robert Kern <[EMAIL PROTECTED]> wrote:
> I do have some Cython code that
> does this. It needs a little bit more work, though. I'll try to push
> it out soonish.
>
That would make me an extremely happy user, I've been looking for this for
years!
I can't imagine I'
Hi
In a recent thread there was an error in how a matrix is reconstructed from
its SVD decomposition. I apologize if this is just an old and settled issue
and I am just adding noise, but I got bitten by numpy's unfamiliar output
myself a long time ago and I see others get confused as well. So what
On Fri, Jul 25, 2008 at 9:39 PM, Keith Goodman <[EMAIL PROTECTED]> wrote:
> On Fri, Jul 25, 2008 at 12:36 PM, Keith Goodman <[EMAIL PROTECTED]>
> wrote:
> > On Fri, Jul 25, 2008 at 12:32 PM, Frank Lagor <[EMAIL PROTECTED]>
> wrote:
> >> Perhaps I do not understand something properly, if so could s
On Fri, Jul 18, 2008 at 12:38 PM, Arnar Flatberg <[EMAIL PROTECTED]>
wrote:
>
>
> On Fri, Jul 18, 2008 at 11:40 AM, Stéfan van der Walt <[EMAIL PROTECTED]>
> wrote:
>
>> 2008/7/18 Arnar Flatberg <[EMAIL PROTECTED]>:
>> > I need to check if my array
On Fri, Jul 18, 2008 at 11:40 AM, Stéfan van der Walt <[EMAIL PROTECTED]>
wrote:
> 2008/7/18 Arnar Flatberg <[EMAIL PROTECTED]>:
> > I need to check if my array (a) is of type `string`. That is, I dont know
> > the number of characters beforehand, so I cant do a.d
Hi
I need to check if my array (a) is of type `string`. That is, I dont know
the number of characters beforehand, so I cant do a.dtype == '|S*' (* =
(max) number of characters)
Looking at my options, I see either a.dtype.kind == 'S' or a.dtype.type ==
np.string_, might be ok. Are these any of the
> This will not work with numpy matrices.* is elementwise mult.
Sorry, disregard that comment
___
Numpy-discussion mailing list
Numpy-discussion@scipy.org
http://projects.scipy.org/mailman/listinfo/numpy-discussion
> i read in some document on the topic of eigenfaces that
> 'Multiplying the sorted eigenvector with face vector results in
> getting the
> face-space vector'
> facespace=sortedeigenvectorsmatrix * adjustedfacematrix
> (when these are numpy.matrices )
This will not work with numpy matrices.
On Sat, Mar 1, 2008 at 2:43 PM, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote:
> hi
> i have a set of images of faces which i make into a 2d array using
> numpy.ndarray
> each row represents a face image
> faces=
> [[ 173. 87. ... 88. 165.]
> [ 158. 103. .. 73. 143.]
> [ 180. 87
On Sat, Mar 1, 2008 at 8:27 AM, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote:
>
> > This example assumes that facearray is an ndarray.(like you described
> > in original post ;-) ) It looks like you are using a matrix.
>
> hi Arnar
> thanks ..
> a few doubts however
>
> 1.when i use say 10 ima
On Thu, Feb 28, 2008 at 3:41 PM, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote:
> > Arnar wrote
>
> > from scipy import linalg
> > facearray-=facearray.mean(0) #mean centering
> > u, s, vt = linalg.svd(facearray, 0)
> > scores = u*s
> > facespace = vt.T
>
> hi Arnar
> when i do this i get these
On Thu, Feb 28, 2008 at 8:17 AM, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote:
> i all
> I am learning PCA method by reading up Turk&Petland papers etc
> while trying out PCA on a set of greyscale images using python, and
> numpy I tried to create eigenvectors and facespace.
>
> i have
> faces
Hi Theodore
Probably not the fastest, but a full example of how you may vectorize your loop.
Ran just one test, and that speeded up the original code.
Example:
from numpy import empty_like
def vectorized_rgb2hsv(im):
"im is a (m, n, 3) array."""
im = im/255.
out = e
Hi Jon
Have you looked at pystream?
http://code.google.com/p/pystream/
Arnar
On Dec 6, 2007 12:39 PM, Jon Wright <[EMAIL PROTECTED]> wrote:
> Hello,
>
> Does anyone have any experience with numpy and using a GPU? eg:
>
> http://developer.nvidia.com/object/cuda.html
>
> ...they seem to have a GPU
ious issue (I
see Gutsy uses 1.0.3). I have tested this behavior on three machines
running Ubunut Feisty with similar result.
On 9/17/07, Travis E. Oliphant <[EMAIL PROTECTED]> wrote:
> Arnar Flatberg wrote:
> > However, when I tried to to insert a 1-dim array with a 'two-di
Hi list
A pretty common use (for me) is to create arrays at the beginning of
my code and then fill in parts as I go along. Today, my code hit a
segmentation fault. The error was that an index-vector ,that usually
is a list with several members, now contained only one member and I
tried to insert a
23 matches
Mail list logo
