On 2006-10-18 14:15:17 +0200, Sssasss wrote: > Fredrik Lundh wrote: > > "Sssasss" wrote: > > > > > I wan't to multiply two square matrixes, and i don't understand why it > > > doesn't work. > > > > > > def multmat(A,B): > > > "A*B" > > > if len(A)!=len(B): return "error" > > > D=[] > > > C=[] > > > for i in range(len(A)): D.append(0) > > > for i in range(len(A)): C.append(D) > > > > append doesn't copy data, so you're basically adding len(A) references to > > the same D list to C. for more on this, see: > > > > http://pyfaq.infogami.com/how-do-i-create-a-multidimensional-list > > > > </F> > > Ok!! Tank you very much, i understand now.
You might also want to look at numpy/numarray. Gerrit. -- http://mail.python.org/mailman/listinfo/python-list
