[Numpy-discussion] Select-based median (in light of code freeze)

2012-07-15 Thread Mike Ressler
Hi, A couple of years ago there was a flurry of work partially at my instigation at SciPy 2009 to build a better median function based on a select algorithm rather than a sort algorithm. It seemed that it had progressed quite far, but the code in lib/function_base.py still uses a sort. Has the

Re: [Numpy-discussion] Select-based median (in light of code freeze)

2012-07-15 Thread Mike Ressler
On Sun, Jul 15, 2012 at 2:40 PM, Charles R Harris charlesr.har...@gmail.com wrote: I was thinking of adding quickselect, but if you have made a start ... go for it. This is territory where I personally am fearful to tread - I'm no developer, but I am an awfully good alpha/beta tester! I can go

Re: [Numpy-discussion] possible enhancement to getitem?

2012-06-08 Thread Mike Ressler
On 08/06/12 14:14, Neal Becker wrote: The fact that this proposed numpy behavior would not match python list behavior holds little weight for me.  I would still favor this change, unless it added significant overhead.  My opinion, of course. As a Joe User, I think using the [-2:2] syntax

[Numpy-discussion] A better median function?

2009-08-21 Thread Mike Ressler
I presented this during a lightning talk at the scipy conference yesterday, so again, at the risk of painting myself as a flaming idiot: - Wanted: A Better/Faster median() Function numpy implementation uses simple sorting algorithm: Sort all the data using the .sort() method

Re: [Numpy-discussion] A better median function?

2009-08-21 Thread Mike Ressler
Hi, On Fri, Aug 21, 2009 at 11:33 AM, Matthew Brettmatthew.br...@gmail.com wrote: Nicolas investigated algorithms that find the lower (or upper) median value.  The lower median is the median iff there are an odd number of entries in our list, or the lower of the central values in the sort,

Re: [Numpy-discussion] Bugs in histogram and matplotlib-hist

2008-11-12 Thread Mike Ressler
On Wed, Nov 12, 2008 at 4:30 AM, Scott Sinclair [EMAIL PROTECTED] wrote: Mike Ressler [EMAIL PROTECTED] 11/12/08 1:19 AM I did an update to a Fedora 9 workstation yesterday that included updating numpy to 1.2.0 and matplotlib 0.98.3 (python version is They reported that the Fedora 9

[Numpy-discussion] Solved Re: Bugs in histogram and matplotlib-hist

2008-11-12 Thread Mike Ressler
On Wed, Nov 12, 2008 at 2:09 PM, David Huard [EMAIL PROTECTED] wrote: Mike, before patching, please take a look at the tickets related to histogram on the numpy trac. Previously, histogram returned only used the left bin edges and it caused a lot of problems with outliers and normalization.

Re: [Numpy-discussion] Going toward time-based release ?

2008-05-12 Thread Mike Ressler
On Mon, May 12, 2008 at 5:41 AM, David Cournapeau [EMAIL PROTECTED] wrote: Joris De Ridder wrote: As Mike, I'm a bit sceptic about the whole idea. The current way doesn't seem broken, so why fix it? If the recent events do not show that something went wrong, I don't know what will

Re: [Numpy-discussion] Going toward time-based release ?

2008-05-11 Thread Mike Ressler
On Sun, May 11, 2008 at 7:59 PM, David Cournapeau [EMAIL PROTECTED] wrote: Hi, I would like to know how people feel about going toward a time-based release process for numpy (and scipy). -1 I'm just a common user, but please, no. The big Linux distros do this and it drives me nuts.

Re: [Numpy-discussion] Slicing/selection in multiple dimensions simultaneously

2007-09-11 Thread Mike Ressler
Thanks, Robert, for the quick response. On 9/11/07, Robert Kern [EMAIL PROTECTED] wrote: There are operations you can express with this form that you couldn't if the behavior that you expected were the case whereas you can get the result you want relatively straightforwardly. In [6]:

Re: [Numpy-discussion] Issues with the memmap object

2007-06-18 Thread Mike Ressler
What versions of python and numpy are you using? On 6/18/07, Sturla Molden [EMAIL PROTECTED] wrote: Problem 3: No 64 bit support on Windows or Linux: On Linux, large files must be memory mapped using mmap64 (or mmap2 if 4k boundaries are acceptable). On Windows,

[Numpy-discussion] Six-legged feature in median function

2007-05-23 Thread Mike Ressler
Bumped into the following in numpy-1.0.2 and 1.0.3 (of course :-) on both 32-bit and 64-bit linux boxes: import numpy as nm a=nm.zeros(100,dtype='Int32')-3 nm.median(a) -3.0 a=nm.zeros(100,dtype='Int16')-3 nm.median(a) Warning: overflow encountered in short_scalars 2768.0

Re: [Numpy-discussion] Managing Rolling Data

2007-02-21 Thread Mike Ressler
On 2/21/07, Alexander Michael [EMAIL PROTECTED] wrote: ... T is to large to fit in memory, so I need to load up H, perform my calculations, pop the oldest N x P slice and push the newest N x P slice into the data cube. What's the best way to do this that will maintain fast computations along