# Find where the Nan's are in an array/list import numpy import math somenumbers = [1,2,3,numpy.nan,5,6,numpy.nan,8,9,10] nanlist = [] for i in range(0,len(somenumbers)): if numpy.isnan(somenumbers[i]): nanlist.append(i) print nanlist nonans = numpy.delete(somenumbers,nanlist) print nonans