Charles R Harris wrote:
On Wed, Jan 8, 2014 at 2:39 PM, Julian Taylor jtaylor.deb...@googlemail.com
wrote:
...
Another function that could be useful is a |a|**2 function, abs2 perhaps.
Chuck
I use mag_sqr all the time. It should be much faster for complex, if computed
via:
x.real**2
On 08/01/14 21:39, Julian Taylor wrote:
An issue is software emulation of real fma. This can be enabled in the
test ufunc with npfma.set_type(libc).
This is unfortunately incredibly slow about a factor 300 on my machine
without hardware fma.
This means we either have a function that is fast
Hi,
It happen frequently that NumPy isn't compiled with all instruction
that is available where it run. For example in distro. So if the
decision is made to use the fast version when we don't use the newer
instruction, the user need a way to know that. So the library need a
function/attribute to
On 8 January 2014 22:39, Julian Taylor jtaylor.deb...@googlemail.comwrote:
As you can see even without real hardware support it is about 30% faster
than inplace unblocked numpy due better use of memory bandwidth. Its
even more than two times faster than unoptimized numpy.
I have an i5, and
On Thu, Jan 9, 2014 at 3:54 PM, Daπid davidmen...@gmail.com wrote:
On 8 January 2014 22:39, Julian Taylor jtaylor.deb...@googlemail.comwrote:
As you can see even without real hardware support it is about 30% faster
than inplace unblocked numpy due better use of memory bandwidth. Its
even
On Thu, Jan 9, 2014 at 3:50 PM, Frédéric Bastien no...@nouiz.org wrote:
Hi,
It happen frequently that NumPy isn't compiled with all instruction
that is available where it run. For example in distro. So if the
decision is made to use the fast version when we don't use the newer
instruction,
On Thu, Jan 9, 2014 at 3:30 PM, Julian Taylor
jtaylor.deb...@googlemail.com wrote:
On Thu, Jan 9, 2014 at 3:50 PM, Frédéric Bastien no...@nouiz.org wrote:
How hard would it be to provide the choise to the user? We could
provide 2 functions like: fma_fast() fma_prec() (for precision)? Or
this
Good questions where do we stop.
I think as you that the fma with guarantees is a good new feature. But
if this is made available, people will want to use it for speed. Some
people won't like to use another library or dependency. They won't
like to have random speed up or slow down. So why not
On 10.01.2014 01:49, Frédéric Bastien wrote:
Do you know if those instruction are automatically used by gcc if we
use the good architecture parameter?
they are used if you enable -ffp-contract=fast. Do not set it to `on`
this is an alias to `off` due to the semantics of C.
-ffast-math
