deLenn wrote: > Hi, > > Does scipy have an equivalent to Matlab's 'find' function, to list the > indices of all nonzero elements in a sparse matrix?
You will want to ask scipy questions on the scipy list. http://www.scipy.org/Mailing_Lists There is no explicit interface on sparse matrix objects to expose the indices of the nonzero elements. A different implementation would have to be written for each type of sparse matrix format. However, if one can spare the memory, one can convert to the coordinate list format and read the row and column indices from that object. In [1]: from scipy.sparse import lil_matrix In [2]: A = lil_matrix((3,3)) In [3]: A[1,2] = 10 In [4]: A[2,0] = -10 In [5]: Acoo = A.tocoo() In [6]: Acoo.row Out[6]: array([2, 1]) In [7]: Acoo.col Out[7]: array([0, 2]) -- Robert Kern "I have come to believe that the whole world is an enigma, a harmless enigma that is made terrible by our own mad attempt to interpret it as though it had an underlying truth." -- Umberto Eco -- http://mail.python.org/mailman/listinfo/python-list