Comparing Columns Function

I am trying to write a function in Python that takes in two inputs: a single list from a list of lists (called row) a 2D array formatted as a list of lists (called A). I want

Solution 1:

maybe like this

defcompcols(row, A):
    for i in A:
        if row[0]==i[0]:
            for j, k inzip(row, i):
                if j==0and k!=0:
                    print row

Solution 2:

So you get a list index is out of range of that line if row[j]==0 and A[i][j]!=0:. j is by construction in range(len(row)) so the error should not come from row[j]. On previous line, you allready have if row[0]==A[i][0]: so it should not come from A[i].

I suspect it comes from A[i] having less elements that row. You should add a test to be sure :

defcompcols(row, A):
    for i inrange(len (A)):
        if (len(A[i]) < len(row):
            raise Exception("Line %d len(A[i]) %d - len(row) %d"
                            % (i, len(A[i]), len(row)))
        for j inrange(len(row)):
            if row[0]==A[i][0]:
                if row[j]==0and A[i][j]!=0:
                    print row