[Tutor] Linear Algebra weirdness

[Kent Johnson]

On Thu, Feb 26, 2009 at 12:32 AM, Mr Gerard Kelly
<gerard.kelly at uqconnect.edu.au> wrote:
> I am getting some very strange behaviour from the Linear Algebra module.
>
> Look at this code:
>
> from LinearAlgebra import *
>
> a=5
> print a
>
> And look at the output that I get when I run it:
>
> 50.0
> 0.0
> 0.25
> 0.0
> 0.5
> 0.0
> 0.75
> 0.0
> 1.0
> [[  2.50000000e-01  -2.50000000e-01  -4.99993750e-01 ...,
>    3.73459082e+01   3.75116710e+01   3.76764961e+01]
>  [  5.00000000e-01  -5.00000000e-01  -6.25000000e-06 ...,
>   -4.99993797e-01  -2.49373966e-03   4.99993766e-01]
>  [  7.50000000e-01  -7.50000000e-01   0.00000000e+00 ...,
>   -7.50000000e-01   0.00000000e+00   7.50000000e-01]
>  [  1.00000000e+00  -1.00000000e+00   0.00000000e+00 ...,
>   -1.00000000e+00   0.00000000e+00   1.00000000e+00]]
> 5
>
>
> Apparently Linear Algebra is giving me the output of another program along with the output for this one. Of course I don't need Linear Algebra to print the number 5, but I've been trying to make a program that uses Linear Algebra, and I'm always having the output come out twice each time I run it. When I edit the program, it always gives me the old output before the new output, even if I edit it right down to something as simple as "a=5, print a".

Is this the LinearAlgebra package from Numeric? It's helpful if you
don't assume we know what you are talking about :-) If so, shouldn't
it be something like
  from Numeric.LinearAlgebra import *
?

Anyway my guess is that you have another program called
LinearAlgebra.py in your python path. *That* program probably has the
correct import, but it also does some calculations and prints the
result. Try this:
import LinearAlgebra
print LinearAlgebra.__file__

to find out what you are really importing.

Kent