[Numpy-discussion] simple vector->matrix question

[Warren Weckesser]

On Thu, Oct 6, 2011 at 7:08 AM, Neal Becker <ndbecker2 at gmail.com> wrote:

> Given a vector y, I want a matrix H whose rows are
>
> y - x0
> y - x1
> y - x2
> ...
>
>
> where x_i are scalars
>
> Suggestion?
>
>

In [15]: import numpy as np

In [16]: y = np.array([10.0, 20.0, 30.0])

In [17]: x = np.array([0, 1, 2, 4])

In [18]: H = y - x[:, np.newaxis]

In [19]: H
Out[19]:
array([[ 10.,  20.,  30.],
       [  9.,  19.,  29.],
       [  8.,  18.,  28.],
       [  6.,  16.,  26.]])


Warren



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