exception - In python numpy least squares, why a singular normal matrix does NOT raise LinAlgError? -

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solving a.x = b least squares. given :

import numpy np a=[[1,0],[0,0]] b=[1,0] x=np.linalg.lstsq(a, b)     # x = 1/(at.a) * (at.b) print x[0]  # [ 1.  0.]

at.a a, , det(a)=0 --> singular. there infinity of solutions; [1,0] one.

why lstsq doesn't raise np.linalg.linalg.linalgerror ? doc says "if computation not converge.". not case ?

does have simple example exception raised lstsq ?


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