Zachary Pincus wrote: >>>> In a 1-d array, find the first point where all subsequent points >>>> have values >>>> less than a threshold, T. >>> >>> Maybe something like: >>> >>> last_greater = numpy.arange(arr.shape)[arr >= T][-1] >>> first_lower = last_greater + 1 >>> >>> There's probably a better way to do it, without the arange, though... >> >> I'm trying to find the first point in a power spectrum such that all >> subsequent >> points are below some level. I've started with: >> >> db is my power spectrum in dB, It is already reversed. >> >> mag = np.maximum.accumulate (db) - db[-1] >> >> Now all I need is to find the first point such that mag < -50. How >> to do this >> efficiently? > > Right -- that's what I showed above. Find the last point in mag that > is >= -50, and by definition the next point is the first point such > that the remainder of mag is < -50.
But where is numpy's 'find_first' function? I can't seem to find it so I had to make my own in C++. _______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@scipy.org http://mail.scipy.org/mailman/listinfo/numpy-discussion