Multiply a Column X61103

Statement

Write a function $prod\_col(i, m)$ that receives the index $i$ of one column of a matrix of int’s $m$ and returns the product of all the integers in that column. The matrix of int’s is represented as a tuple of rows, each row being, in turn, a tuple of int’s. If $m$ has $n$ columns, we are guaranteed that $0 \leq i < n$ .

Observation

Observe that $0 \leq i < n$ implies that the rows of $m$ , if any, have that column and are hence nonempty, but nothing else.

Sample session

>>> prod_col(0, ((8, 0, 2, -1), (4, 3, 2, 1), (10, 11, -11, -10)))
320
>>> prod_col(0, ((8, 0, 2, -1), (4, 3, 2, 1), (10, 11, -11, -10))) + prod_col(2, ((8, 0, 2, -1), (4, 3, 2, 1), (10, 11, -11, -10)))
276
>>> prod_col(1, ((8, 0, 2, -1), (4, 3, 2, 1), (10, 11, -11, -10)))
0

Information

Author: José Luis Balcázar
Language: English
Official solutions: Python
User solutions: Python