[sage-support] Re: Matrix multiplication over finite fields

2007-10-11 Thread Simon King
Dear Joel, On Oct 9, 7:28 pm, Joel B. Mohler [EMAIL PROTECTED] wrote: snip Hmm, that's a pretty big improvement over the SAGE time above. I suspect that we will have to work a lot harder than either of our optimizations have so far. After slightly improving my MeatAxe extension type for

[sage-support] Re: Question: What's special about 994?

2007-10-11 Thread kcrisman
I figured that x was being treated differently in some ways, because I always had to re-variabilize (is that a word?) x in a related context. I didn't realize that it was symbolic all the way through, though that would definitely be very inefficient. However, I really hate using lambda or

[sage-support] strange behaviour when converting a numpy matrix to a sage one.

2007-10-11 Thread adrianmatematico
sage: import numpy sage: numpy.array([[1,2,3],[4,5,6],[7,8,9]],'f') array([[ 1., 2., 3.], [ 4., 5., 6.], [ 7., 8., 9.]], dtype=float32) sage: a=numpy.array([[1,2,3],[4,5,6],[7,8,9]],'f') sage: matrix(a) [ 2.0047311 512.000122547 8192.0019722] [

[sage-support] Re: bug in matrix

2007-10-11 Thread Mike Hansen
Hello, Are you running a 64-bit machine? I looked at the code, and the problem seems to come from the fact that it is doing a naive check on the type of the numpy array; it is currently assuming that your float32 array is a float64 array which is why you are getting the strange results you are.

[sage-support] Re: bug in matrix

2007-10-11 Thread Mike Hansen
Hello, I've attached a patch that fixes the issues that you've mentioned. To apply it, run hg_sage.patch('/path/to/856.patch') from SAGE, exit SAGE, and then run ./sage -br . There still is some work to be done with numpy support -- for example, getting the numpy integer types to play well with