Dinesh B Vadhia wrote: > A NumPy matrix (because we have to perform a dot matrix multiplication > prior to creating an inverted index).
Maybe something like this? from collections import defaultdict a = array(...) index = defaultdict(list) for i, x in ndenumerate(a): index[x].append(i) This creates a dict whose keys are the values in the array and values are lists of indices where the value appears. I don't know how your sparse matrix is represented but maybe you need some kind of filter in the loop to only record meaningful values. http://www.scipy.org/Numpy_Example_List_With_Doc#ndenumerate Kent > > ----- Original Message ----- > > Dinesh B Vadhia wrote: > > Sure! To create an inverted index of a very large matrix (M x N with > > M<>N and M>10m rows). Most times the matrix will be sparse but > > sometimes it won't be. Most times the matrix will consist of 0's and > > 1's but sometimes it won't. > > How is the matrix represented? Is it in a numpy array? a dict? or... > > Kent > > Dinesh B Vadhia wrote: > > > Hello! Anyone know of any example/cookbook code for implementing > > > inverted indexes? > > > > Can you say more about what you are trying to do? > _______________________________________________ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
