In [1]: import numpy

In [2]: x = numpy.array([5,6,7,8,10,11,12,14])

In [3]: x
Out[3]: array([ 5,  6,  7,  8, 10, 11, 12, 14])

In [4]: x > 10
Out[4]: array([False, False, False, False, False,  True,  True,  True], dtype=bool)

In [5]: ['Y' if y > 10 else 'N' for y in x]
Out[5]: ['N', 'N', 'N', 'N', 'N', 'Y', 'Y', 'Y']

In [6]: [{True: 'Y', False: 'N'}[y] for y in x > 10]
Out[6]: ['N', 'N', 'N', 'N', 'N', 'Y', 'Y', 'Y']