On Tue, 12 Aug 2008 10:37:51 -0400, Gong, Shawn (Contractor) wrote:
> The following array manipulation takes long time because I can't find
> ways to do in row/column, and have to do cell by cell. Would you check
> to see if there is a nicer/faster way for this non-linear operation?
>
> for i in
2008/8/12 Nadav Horesh <[EMAIL PROTECTED]>:
> from numpy import *
>
> a = sqrt(maximum(0, a**2-repeat(b*c, columns).reshape(columns, rows)))
better:
import numpy as np
a = np.sqrt(np.maximum(0.0, a**2-(b*c)[np.newaxis,:]))
This doesn't have to make a temporary the size of a; instead
broadcastin
thank you, Nadav
Shawn
-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Nadav Horesh
Sent: Tuesday, August 12, 2008 11:58 AM
To: Discussion of Numerical Python
Subject: RE: [Numpy-discussion] non-linear array manipulation
from numpy import *
a = sqrt
from numpy import *
a = sqrt(maximum(0, a**2-repeat(b*c, columns).reshape(rows, columns)))
Nadav
-הודעה מקורית-
מאת: [EMAIL PROTECTED] בשם Gong, Shawn (Contractor)
נשלח: ג 12-אוגוסט-08 17:37
אל: Discussion of Numerical Python
נושא: [Numpy-discussion] non-linear array manipulation
from numpy import *
a = sqrt(maximum(0, a**2-repeat(b*c, columns).reshape(columns, rows)))
Nadav.
-הודעה מקורית-
מאת: [EMAIL PROTECTED] בשם Gong, Shawn (Contractor)
נשלח: ג 12-אוגוסט-08 17:37
אל: Discussion of Numerical Python
נושא: [Numpy-discussion] non-linear array manipulation
hi
hi list,
The following array manipulation takes long time because I can't find
ways to do in row/column, and have to do cell by cell. Would you check
to see if there is a nicer/faster way for this non-linear operation?
for i in range(rows):
for j in range(columns):
a[i][j] = math.sqrt(
