Ross Williamson wrote: > Hi All > > I want to get out the index of values in an array. Normally WHERE > works fine for one conditional statement but it does not work for two > - i.e. > > a = array([0,1,2,3,4,5,6,7,8,9]) > > ind, = where(a > 5) > > Works fine but if I wanted: > > ind = where((a > 5) and (a<8))
Python/numpy wart: for fairly fundamental Python reasons, "and" does not work elementwise so you have to use the "&" operator instead: ind = where((a > 5) & (a<8)) Same for "or" and "|". Parentheses as you have them are essential because of the precedence of the bit operators. Eric > > Then it bugs out with the following message: > > "The truth value of an array with more than one message is ambiguous" > > Any ideas? > > Cheers > > Ross > _______________________________________________ > Numpy-discussion mailing list > Numpy-discussion@scipy.org > http://projects.scipy.org/mailman/listinfo/numpy-discussion _______________________________________________ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
