Re: [Numpy-discussion] Odd-looking long double on windows 32 bit

2011-11-12 Thread Matthew Brett
Hi, On Sat, Nov 12, 2011 at 11:35 PM, Matthew Brett wrote: > Hi, > > Sorry for my continued confusion here.  This is numpy 1.6.1 on windows > XP 32 bit. > > In [2]: np.finfo(np.float96).nmant > Out[2]: 52 > > In [3]: np.finfo(np.float96).nexp > Out[3]: 15 > > In [4]: np.finfo(np.float64).nmant >

[Numpy-discussion] Odd-looking long double on windows 32 bit

2011-11-12 Thread Matthew Brett
Hi, Sorry for my continued confusion here. This is numpy 1.6.1 on windows XP 32 bit. In [2]: np.finfo(np.float96).nmant Out[2]: 52 In [3]: np.finfo(np.float96).nexp Out[3]: 15 In [4]: np.finfo(np.float64).nmant Out[4]: 52 In [5]: np.finfo(np.float64).nexp Out[5]: 11 If there are 52 bits of p

Re: [Numpy-discussion] speeding up the following expression

2011-11-12 Thread Geoffrey Zhu
Hi Warren, On Sat, Nov 12, 2011 at 9:31 AM, Warren Weckesser wrote: > > > On Sat, Nov 12, 2011 at 6:43 AM, wrote: >> >> On Sat, Nov 12, 2011 at 3:36 AM, Geoffrey Zhu wrote: >> > Hi, >> > >> > I am playing with multiple ways to speed up the following expression >> > (it is in the inner loop): >>

Re: [Numpy-discussion] speeding up the following expression

2011-11-12 Thread Warren Weckesser
On Sat, Nov 12, 2011 at 11:16 AM, wrote: > On Sat, Nov 12, 2011 at 11:32 AM, Warren Weckesser > wrote: > > > > > > On Sat, Nov 12, 2011 at 9:59 AM, wrote: > >> > >> On Sat, Nov 12, 2011 at 10:31 AM, Warren Weckesser > >> wrote: > >> > > >> > > >> > On Sat, Nov 12, 2011 at 6:43 AM, wrote: > >>

Re: [Numpy-discussion] speeding up the following expression

2011-11-12 Thread josef . pktd
On Sat, Nov 12, 2011 at 11:32 AM, Warren Weckesser wrote: > > > On Sat, Nov 12, 2011 at 9:59 AM, wrote: >> >> On Sat, Nov 12, 2011 at 10:31 AM, Warren Weckesser >> wrote: >> > >> > >> > On Sat, Nov 12, 2011 at 6:43 AM, wrote: >> >> >> >> On Sat, Nov 12, 2011 at 3:36 AM, Geoffrey Zhu >> >> wrot

Re: [Numpy-discussion] speeding up the following expression

2011-11-12 Thread Warren Weckesser
On Sat, Nov 12, 2011 at 9:59 AM, wrote: > On Sat, Nov 12, 2011 at 10:31 AM, Warren Weckesser > wrote: > > > > > > On Sat, Nov 12, 2011 at 6:43 AM, wrote: > >> > >> On Sat, Nov 12, 2011 at 3:36 AM, Geoffrey Zhu > wrote: > >> > Hi, > >> > > >> > I am playing with multiple ways to speed up the fo

Re: [Numpy-discussion] speeding up the following expression

2011-11-12 Thread josef . pktd
On Sat, Nov 12, 2011 at 10:31 AM, Warren Weckesser wrote: > > > On Sat, Nov 12, 2011 at 6:43 AM, wrote: >> >> On Sat, Nov 12, 2011 at 3:36 AM, Geoffrey Zhu wrote: >> > Hi, >> > >> > I am playing with multiple ways to speed up the following expression >> > (it is in the inner loop): >> > >> > >>

Re: [Numpy-discussion] speeding up the following expression

2011-11-12 Thread Warren Weckesser
On Sat, Nov 12, 2011 at 6:43 AM, wrote: > On Sat, Nov 12, 2011 at 3:36 AM, Geoffrey Zhu wrote: > > Hi, > > > > I am playing with multiple ways to speed up the following expression > > (it is in the inner loop): > > > > > > C[1:(M - 1)]=(a * C[2:] + b * C[1:(M-1)] + c * C[:(M-2)]) > > > > where C

Re: [Numpy-discussion] speeding up the following expression

2011-11-12 Thread josef . pktd
On Sat, Nov 12, 2011 at 3:36 AM, Geoffrey Zhu wrote: > Hi, > > I am playing with multiple ways to speed up the following expression > (it is in the inner loop): > > > C[1:(M - 1)]=(a * C[2:] + b * C[1:(M-1)] + c * C[:(M-2)]) > > where C is an array of about 200-300 elements, M=len(C), a, b, c are

[Numpy-discussion] speeding up the following expression

2011-11-12 Thread Geoffrey Zhu
Hi, I am playing with multiple ways to speed up the following expression (it is in the inner loop): C[1:(M - 1)]=(a * C[2:] + b * C[1:(M-1)] + c * C[:(M-2)]) where C is an array of about 200-300 elements, M=len(C), a, b, c are scalars. I played with numexpr, but it was way slower than directly