numpy (matrix solver) - python vs. matlab

[Paul Rubin]

someone <newsboost at gmail.com> writes:
>> A is not just close to singular: it's singular!
> Ok. When do you define it to be singular, btw?

Singular means the determinant is zero, i.e. the rows or columns
are not linearly independent.  Let's give names to the three rows:

  a = [1 2 3]; b = [11 12 13]; c = [21 22 23].

Then notice that c = 2*b - a.  So c is linearly dependent on a and b.
Geometrically this means the three vectors are in the same plane,
so the matrix doesn't have an inverse.

>>> Which is the most accurate/best, even for such a bad matrix? 

What are you trying to do?  If you are trying to calculate stuff
with matrices, you really should know some basic linear algebra.