I didn't look into that but it definitely sounds interesting. Especially
as the coefficient manipulation is mildly unstable for higher
derivatives. Need to work out the math first though ;). Thanks for the hint.
On 25.07.2011 15:59, Charles R Harris wrote:
> On Sun, Jul 24, 2011 at 5:10 PM, Rober
On Sun, Jul 24, 2011 at 5:10 PM, Robert Elsner wrote:
> Boiled it down a bit more to only include code that actually takes time.
> First time around I found the other variant more instructive because it
> shows the discrepancy between the DCT and the loop but might be
> confusing. Thus here the b
Mon, 25 Jul 2011 12:30:34 +0200, Robert Elsner wrote:
> Thanks for the hint. I thought about Cython myself but I was unable to
> get even the slightest speed gain out of it. Here is the equivalent
> Cython code with the timing and setup.py. I typed (I think). Am I
> missing something obvious?
Cyth
Yes I did. Slicing and Cython do not mix too well. Using an explicit
loop fixes the problem. In case anybody is interested the code is attached.
Thanks for your help
Robert
On 25.07.2011 12:30, Robert Elsner wrote:
> Thanks for the hint. I thought about Cython myself but I was unable to
> get eve
Thanks for the hint. I thought about Cython myself but I was unable to
get even the slightest speed gain out of it.
Here is the equivalent Cython code with the timing and setup.py. I typed
(I think). Am I missing something obvious?
Cheers
Robert
On 25.07.2011 01:38, Joon Ro wrote:
> For those ca
For those cases where you cannot vectorize the operation, numpy is usually
does not help much.
Try using Cython. You will be able to compile the part of the code and the
loop will be much faster (can be more than 100 times faster).
http://docs.cython.org/
-Joon
On Sun, 24 Jul 2011 18:10:14
Boiled it down a bit more to only include code that actually takes time.
First time around I found the other variant more instructive because it
shows the discrepancy between the DCT and the loop but might be
confusing. Thus here the bare minimum that correctly calculates the
coefficients of the fi
Hey Everybody,
I am approximating the derivative of nonperiodic functions on [-1,1]
using Chebyshev polynomials. The implementation is straightforward and
works well but is painfully slow. The routine wastes most of its time on
a trivial operation (see comment in the code)
Unfortunately the spectr
