Question : Matrices subtraction similar to numpy

[rohitjoshi]

In numpy y-mu returns as below

mu=[-1.35900258, -0.00274826, -0.60259734]
y=[[-1.16850298],
 [-0.71405641],
 [-1.84973747]]

r = y-mu
print("y-mu=" + str(r))
y-mu = [[ 0.1904996  -1.16575472 -0.56590564]
 [ 0.64494618 -0.71130814 -0.11145907]
 [-0.49073488 -1.8469892  -1.24714013]]

How do I achieve same in ndarray?

mu=[-0.25304218713684945, 0.12751433863551823, 0.3773315624850666]
y= [[0.41651350674857823]]
y-mu gives error 
thread 'main' panicked at 'ndarray: could not broadcast array from shape: [3] to: [1, 1]'

[vbarrielle]

You probably want to use broadcasting.

[rohitjoshi]

I tried few ways without any success. Would appreciate your help.

[jturner314]

See #437 for a similar question, in particular this response. Basically, one solution is to broadcast the left array (y in your example) to the size of the result, and then perform the operation.

[jturner314]

@rohitjoshi Do you have any more questions about this? Otherwise, I'll close this issue.

[rohitjoshi]

No, thx