How can I filter a numpy array based on another numpy array?

Question

I have two numpy arrays that were created by splitting one array. X has 7 columns and Y has 1 column.

I am filtering X with :

X[(X[:,2] != 0) & (X[:,1] != 0) & (X[:,3] != 0) & (X[:,4] != 0)]

This gives me the correct rows of X. How do I get the rows in Y with the matching row indices?

Joran Beasley · Accepted Answer · 2016-04-09 02:13:20Z

1

the same way you get X

mask = (X[:,2] != 0) & (X[:,1] != 0) & (X[:,3] != 0) & (X[:,4] != 0)
# mask is a list of [True,False,True,...]
print X[mask]
print Y[mask]

answered Apr 9, 2016 at 2:13

Joran Beasley

114k13 gold badges167 silver badges187 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Thanks Joran. This was just what I needed.