# [Numpy-discussion] Speed degression?

Steffen Loeck steffen.loeck at gmx.de
Tue Jul 4 08:19:24 CDT 2006

```Hi all,

i made some speed tests using the sin-function and the %-operation to compare
Numeric, numpy 0.9.8 and numpy 0.9.9.2732.
As result the latest numpy version seems to be very slow in comparison to the
two other candidates.

Results (in usec per loop):
sin-array            mod-array

Numeric                                134                   18

numpy 0.9.8                             97                   55

numpy 0.9.9.2732                       204                  316

numpy 0.9.8 + math                      38

numpy 0.9.9.2732 + math                161

Numeric + math                          23

The used scripts can be found at the end.

Can anyone verify my results and explain the observed speed degression?

Thanks,
Steffen

sin-scripts:

/usr/lib/python2.3/timeit.py -s "from Numeric import sin,zeros,arange;
x=zeros(10, 'd'); x[0]=0.1" "for i in arange(9): x[i+1]=sin(x[i])"

/usr/lib/python2.3/timeit.py -s "from numpy import sin,zeros,arange;
x=zeros(10, 'd'); x[0]=0.1" "for i in arange(9): x[i+1]=sin(x[i])"

/usr/lib/python2.3/timeit.py -s "from math import sin; from numpy import
zeros,arange; x=zeros(10, 'd');x[0]=0.1" "for i in arange(9):
x[i+1]=sin(x[i])"

/usr/lib/python2.3/timeit.py -s "from math import sin; from Numeric import
zeros,arange; x=zeros(10, 'd'); x[0]=0.1" "for i in arange(9):
x[i+1]=sin(x[i]
)"

%-scripts

/usr/lib/python2.3/timeit.py -s "from Numeric import zeros,arange; x=zeros(10,
'd'); x[0]=0.1" "for i in arange(9): x[i+1]=(x[i]+1.1)%(1.0)"

/usr/lib/python2.3/timeit.py -s "from numpy import zeros,arange; x=zeros(10,
'd'); x[0]=0.1" "for i in arange(9): x[i+1]=(x[i]+1.1)%(1.0)"

```