numpy.extract and numpy.any functions, is it possible to make it simpler way?

Question

If there is any possibility to make this code simpler, I'd really appreciate it! I am trying to get rid of rows with zeros. The first column is date. If all other columns are zero, they have to be deleted. Number of columns varies.

import numpy as np

condition = [ np.any( list(x)[1:] ) for x in r]
r = np.extract( condition, r )

numpy.extract docs

Answer 1

You can avoid the list comprehension and instead use fancy indexing:

#!/usr/bin/env python
import numpy as np
import datetime
r=np.array([(datetime.date(2000,1,1),0,1),
            (datetime.date(2000,1,1),1,1),
            (datetime.date(2000,1,1),1,0),
            (datetime.date(2000,1,1),0,0),                        
            ])
r=r[r[:,1:].any(axis=1)]
print(r)
# [[2000-01-01 0 1]
#  [2000-01-01 1 1]
#  [2000-01-01 1 0]

if r is an ndarray, then r[:,1:] is a view with the first column removed. r[:,1:].any(axis=1) is a boolean array, which you can then use as a "fancy index"