>>> 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. _______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@scipy.org http://mail.scipy.org/mailman/listinfo/numpy-discussion
