[Numpy-discussion] dot product: large speed difference metween seemingly indentical operations

The functions dot, matmul and tensordot performs the same on a MxN matrix multiplied by length N vector, but very different if the matrix is replaced by a PxQxN array. Why? In [3]: a = rand(100,3) In [4]: a1 = a.reshape(1000,1000,3) In [5]: w = rand(3) In [6]: %timeit a.dot(w) 100 loops,

Re: [Numpy-discussion] [SciPy-Dev] Setting up a dev environment with conda

Hi Luke, For day-to-day development and testing of numpy, I don't bother with either inplace builds *or* installing it -- I just use the magical "runtests.py" script that you'll find in the root of your git checkout. E.g., to build and then test the (possibly modified) source in your current chec

Re: [Numpy-discussion] Making datetime64 timezone naive

On Fri, Oct 16, 2015 at 10:19 AM, Alexander Belopolsky wrote: > Since Guido hates leap seconds, PEP 495 is silent on this issue, but > strictly speaking UTC leap seconds are "folds." AFAICT, a strictly POSIX > system must repeat the same value of time_t when a leap second is > inserted. While

Re: [Numpy-discussion] Interesting discussion on copyrighting files.

On Sat, Oct 17, 2015 at 10:24 AM, wrote: > > On Thu, Oct 15, 2015 at 11:28 PM, Charles R Harris > wrote: >> >> Worth a read at A&D. > > Thanks, it is worth a read. > > Most of the time when I see code copied from scipy or statsmodels, it is > properly attributed. > But every once in a while (lik

Re: [Numpy-discussion] Interesting discussion on copyrighting files.

On Thu, Oct 15, 2015 at 11:28 PM, Charles R Harris < charlesr.har...@gmail.com> wrote: > Worth a read at A&D . > Thanks, it is worth a read. Most of the time when I see code copied from scipy or statsmodels, it is properly attributed. But every once in a