[Numpy-discussion] nan_to_num and bool arrays

2009-12-11 Thread Nicolas Rougier
Hello, Using both numpy 1.3.0 and 1.4.0rc1 I got the following exception using nan_to_num on a bool array, is that the expected behavior ? import numpy Z = numpy.zeros((3,3),dtype=bool) numpy.nan_to_num(Z) Traceback (most recent call last): File stdin, line 1, in module File

[Numpy-discussion] Slicing slower than matrix multiplication?

2009-12-11 Thread Jasper van de Gronde
(Resending without attachment as I don't think my previous message arrived.) I just started using numpy and am very, very pleased with the functionality and cleanness so far. However, I tried what I though would be a simple optimization and found that the opposite was true. Specifically, I had a

Re: [Numpy-discussion] Slicing slower than matrix multiplication?

2009-12-11 Thread Dag Sverre Seljebotn
Jasper van de Gronde wrote: (Resending without attachment as I don't think my previous message arrived.) I just started using numpy and am very, very pleased with the functionality and cleanness so far. However, I tried what I though would be a simple optimization and found that the opposite

Re: [Numpy-discussion] Slicing slower than matrix multiplication?

2009-12-11 Thread Jasper van de Gronde
Dag Sverre Seljebotn wrote: Jasper van de Gronde wrote: I've attached a test file which shows the problem. It also tries adding columns instead of rows (in case the memory layout is playing tricks), but this seems to make no difference. This is the output I got: Dot product: 5.188786

Re: [Numpy-discussion] Slicing slower than matrix multiplication?

2009-12-11 Thread Dag Sverre Seljebotn
Jasper van de Gronde wrote: Dag Sverre Seljebotn wrote: Jasper van de Gronde wrote: I've attached a test file which shows the problem. It also tries adding columns instead of rows (in case the memory layout is playing tricks), but this seems to make no difference. This is the output

Re: [Numpy-discussion] Slicing slower than matrix multiplication?

2009-12-11 Thread Francesc Alted
A Friday 11 December 2009 16:44:29 Dag Sverre Seljebotn escrigué: Jasper van de Gronde wrote: Dag Sverre Seljebotn wrote: Jasper van de Gronde wrote: I've attached a test file which shows the problem. It also tries adding columns instead of rows (in case the memory layout is playing

Re: [Numpy-discussion] [Nipy-devel] Impossibility to build nipy on recent numpy?

2009-12-11 Thread Gael Varoquaux
On Thu, Dec 10, 2009 at 05:19:24PM +0100, Gael Varoquaux wrote: On Thu, Dec 10, 2009 at 10:17:43AM -0600, Robert Kern wrote: OK, so we need to bug report to ubuntu. Anybody feels like doing it, or do I need to go ahead :). It's your problem. :-) That's kinda what I thought. I was just

Re: [Numpy-discussion] nan_to_num and bool arrays

2009-12-11 Thread Keith Goodman
On Fri, Dec 11, 2009 at 12:50 AM, Nicolas Rougier nicolas.roug...@loria.fr wrote: Hello, Using both numpy 1.3.0 and 1.4.0rc1 I got the following exception using nan_to_num on a bool array, is that the expected behavior ? import numpy Z = numpy.zeros((3,3),dtype=bool) numpy.nan_to_num(Z)

Re: [Numpy-discussion] Slicing slower than matrix multiplication?

2009-12-11 Thread Bruce Southey
On 12/11/2009 10:03 AM, Francesc Alted wrote: A Friday 11 December 2009 16:44:29 Dag Sverre Seljebotn escrigué: Jasper van de Gronde wrote: Dag Sverre Seljebotn wrote: Jasper van de Gronde wrote: I've attached a test file which shows the problem. It also tries

Re: [Numpy-discussion] nan_to_num and bool arrays

2009-12-11 Thread Nicolas Rougier
I've created a ticket (#1327). Nicolas On Dec 11, 2009, at 17:21 , Keith Goodman wrote: On Fri, Dec 11, 2009 at 12:50 AM, Nicolas Rougier nicolas.roug...@loria.fr wrote: Hello, Using both numpy 1.3.0 and 1.4.0rc1 I got the following exception using nan_to_num on a bool array, is that

Re: [Numpy-discussion] Slicing slower than matrix multiplication?

2009-12-11 Thread Francesc Alted
A Friday 11 December 2009 17:36:54 Bruce Southey escrigué: On 12/11/2009 10:03 AM, Francesc Alted wrote: A Friday 11 December 2009 16:44:29 Dag Sverre Seljebotn escrigué: Jasper van de Gronde wrote: Dag Sverre Seljebotn wrote: Jasper van de Gronde wrote: I've attached a test file which

[Numpy-discussion] December Webinar: SciPy India with Travis Oliphant

2009-12-11 Thread Amenity Applewhite
Next Friday Enthought will be hosting our monthly Scientific Computing with Python Webinar: Summary of SciPy India Friday December 18 1pm CST/ 7pm UTC Register at GoToMeeting Enthought President Travis Oliphant is currently in Kerala, India as the keynote speaker at SciPy India 2009. Due to a

Re: [Numpy-discussion] nan_to_num and bool arrays

2009-12-11 Thread Bruce Southey
On 12/11/2009 10:21 AM, Keith Goodman wrote: On Fri, Dec 11, 2009 at 12:50 AM, Nicolas Rougier nicolas.roug...@loria.fr wrote: Hello, Using both numpy 1.3.0 and 1.4.0rc1 I got the following exception using nan_to_num on a bool array, is that the expected behavior ? import

Re: [Numpy-discussion] nan_to_num and bool arrays

2009-12-11 Thread Robert Kern
On Fri, Dec 11, 2009 at 13:11, Bruce Southey bsout...@gmail.com wrote: As documented, nan_to_num returns a float so it does not return the input unchanged. I think that is describing the current behavior rather than documenting the intent of the function. Given the high level purpose of the

Re: [Numpy-discussion] nan_to_num and bool arrays

2009-12-11 Thread Bruce Southey
On 12/11/2009 01:33 PM, Robert Kern wrote: On Fri, Dec 11, 2009 at 13:11, Bruce Southeybsout...@gmail.com wrote: As documented, nan_to_num returns a float so it does not return the input unchanged. Sorry for my mistake: Given an int input, np.nan_to_num returns an int dtype

Re: [Numpy-discussion] nan_to_num and bool arrays

2009-12-11 Thread Keith Goodman
On Fri, Dec 11, 2009 at 12:08 PM, Bruce Southey bsout...@gmail.com wrote: On 12/11/2009 01:33 PM, Robert Kern wrote: On Fri, Dec 11, 2009 at 13:11, Bruce Southeybsout...@gmail.com  wrote: As documented, nan_to_num returns a float so it does not return the input unchanged. Sorry for my

Re: [Numpy-discussion] nan_to_num and bool arrays

2009-12-11 Thread Robert Kern
On Fri, Dec 11, 2009 at 14:41, Keith Goodman kwgood...@gmail.com wrote: On Fri, Dec 11, 2009 at 12:08 PM, Bruce Southey bsout...@gmail.com wrote: So I agree that it should leave the input untouched when a non-float dtype is used for some array-like input. Would only one line need to be

Re: [Numpy-discussion] nan_to_num and bool arrays

2009-12-11 Thread Keith Goodman
On Fri, Dec 11, 2009 at 1:14 PM, Robert Kern robert.k...@gmail.com wrote: On Fri, Dec 11, 2009 at 14:41, Keith Goodman kwgood...@gmail.com wrote: On Fri, Dec 11, 2009 at 12:08 PM, Bruce Southey bsout...@gmail.com wrote: So I agree that it should leave the input untouched when a non-float

Re: [Numpy-discussion] nan_to_num and bool arrays

2009-12-11 Thread Robert Kern
On Fri, Dec 11, 2009 at 16:09, Keith Goodman kwgood...@gmail.com wrote: On Fri, Dec 11, 2009 at 1:14 PM, Robert Kern robert.k...@gmail.com wrote: On Fri, Dec 11, 2009 at 14:41, Keith Goodman kwgood...@gmail.com wrote: On Fri, Dec 11, 2009 at 12:08 PM, Bruce Southey bsout...@gmail.com wrote:

Re: [Numpy-discussion] nan_to_num and bool arrays

2009-12-11 Thread Keith Goodman
On Fri, Dec 11, 2009 at 2:22 PM, Robert Kern robert.k...@gmail.com wrote: On Fri, Dec 11, 2009 at 16:09, Keith Goodman kwgood...@gmail.com wrote: On Fri, Dec 11, 2009 at 1:14 PM, Robert Kern robert.k...@gmail.com wrote: On Fri, Dec 11, 2009 at 14:41, Keith Goodman kwgood...@gmail.com wrote: On

Re: [Numpy-discussion] nan_to_num and bool arrays

2009-12-11 Thread Keith Goodman
On Fri, Dec 11, 2009 at 3:44 PM, Keith Goodman kwgood...@gmail.com wrote: On Fri, Dec 11, 2009 at 2:22 PM, Robert Kern robert.k...@gmail.com wrote: On Fri, Dec 11, 2009 at 16:09, Keith Goodman kwgood...@gmail.com wrote: On Fri, Dec 11, 2009 at 1:14 PM, Robert Kern robert.k...@gmail.com wrote:

Re: [Numpy-discussion] nan_to_num and bool arrays

2009-12-11 Thread Robert Kern
On Fri, Dec 11, 2009 at 17:44, Keith Goodman kwgood...@gmail.com wrote: On Fri, Dec 11, 2009 at 2:22 PM, Robert Kern robert.k...@gmail.com wrote: On Fri, Dec 11, 2009 at 16:09, Keith Goodman kwgood...@gmail.com wrote: On Fri, Dec 11, 2009 at 1:14 PM, Robert Kern robert.k...@gmail.com wrote: On

Re: [Numpy-discussion] nan_to_num and bool arrays

2009-12-11 Thread Robert Kern
On Fri, Dec 11, 2009 at 18:03, Keith Goodman kwgood...@gmail.com wrote: Ack! The if issubclass(t, _nx.inexact) fix doesn't work. It solves the bool problem but it introduces its own problem since numpy.object_ is not a subclass of inexact: nan_to_num([np.inf])   array([ Inf]) Right. This

Re: [Numpy-discussion] nan_to_num and bool arrays

2009-12-11 Thread Keith Goodman
On Fri, Dec 11, 2009 at 4:06 PM, Robert Kern robert.k...@gmail.com wrote: On Fri, Dec 11, 2009 at 17:44, Keith Goodman kwgood...@gmail.com wrote: On Fri, Dec 11, 2009 at 2:22 PM, Robert Kern robert.k...@gmail.com wrote: On Fri, Dec 11, 2009 at 16:09, Keith Goodman kwgood...@gmail.com wrote: On

Re: [Numpy-discussion] nan_to_num and bool arrays

2009-12-11 Thread Robert Kern
On Fri, Dec 11, 2009 at 18:38, Keith Goodman kwgood...@gmail.com wrote: That seems to work. To avoid changing the input x = np.array(1) x.shape   () y = nan_to_num(x) x.shape   (1,) I moved y = x.copy() further up and switched x's to y's. Here's what it looks like: def nan_to_num(x):

Re: [Numpy-discussion] non-standard standard deviation

2009-12-11 Thread Dr. Phillip M. Feldman
Anne Archibald wrote: 2009/11/29 Dr. Phillip M. Feldman pfeld...@verizon.net: All of the statistical packages that I am currently using and have used in the past (Matlab, Minitab, R, S-plus) calculate standard deviation using the sqrt(1/(n-1)) normalization, which gives a result that

Re: [Numpy-discussion] Slicing slower than matrix multiplication?

2009-12-11 Thread David Cournapeau
On Fri, Dec 11, 2009 at 10:06 PM, Bruce Southey bsout...@gmail.com wrote: Having said that, the more you can vectorize your function, the more efficient it will likely be especially with Atlas etc. One thing to note is that dot uses optimized atlas if available, which makes it quite faster

Re: [Numpy-discussion] Slicing slower than matrix multiplication?

2009-12-11 Thread Hoyt Koepke
One thing to note is that dot uses optimized atlas if available, which makes it quite faster than equivalent operations you would do using purely numpy. I doubt that's the reason here, since the arrays are small, but that's something to keep in mind when performances matter: use dot wherever

Re: [Numpy-discussion] nan_to_num and bool arrays

2009-12-11 Thread Keith Goodman
On Fri, Dec 11, 2009 at 6:38 PM, Robert Kern robert.k...@gmail.com wrote: On Fri, Dec 11, 2009 at 18:38, Keith Goodman kwgood...@gmail.com wrote: That seems to work. To avoid changing the input x = np.array(1) x.shape   () y = nan_to_num(x) x.shape   (1,) I moved y = x.copy() further