Changing values of 1st column of a matrix using take(mymatrix, (0, ), axis=1)

[Tim Hochberg]

Anthony Liu wrote:
> I am talking about the 'take' method of numarray.
> 
> See here for more info:
> 
> http://stsdas.stsci.edu/numarray/Doc/node33.html
> 
> If I initialize a matrix 'mymatrix' by zeros((3,3),
> type="Float64"), I get a 3*3 matrix of all zeros.
> 
> Look:
> 
> 
>>>>from numarray import *
>>>>mymatrix = zeros((3,3), type="Float64")
>>>>mymatrix
> 
> array([[ 0.,  0.,  0.],
>        [ 0.,  0.,  0.],
>        [ 0.,  0.,  0.]])
> 
> 
> I want to change the zeros of only the first column to
> 1's.  In other words, I want to get:
> 
> array([[ 1.,  0.,  0.],
>        [ 1.,  0.,  0.],
>        [ 1.,  0.,  0.]])
> 
> The 'take' method is able to take out the first
> column, but I am not sure if there is a good way of
> changing all values of the first column to 1's.
> 
> Of course, I know that I can achieve my goal pretty
> easily with this:
> 
> for i in range(3): mymatrix[i,0] = 1.0
> 
> I am just wondering if there is an existing numarray
> method that elegantly does it for me.

mymatrix[:,0] = 1.0

> 
> 
> __________________________________________________
> Do You Yahoo!?
> Tired of spam?  Yahoo! Mail has the best spam protection around 
> http://mail.yahoo.com