How to create a row that displays the counts of column entries in a matrix using python/sage?
so here is my matrix:
A = matrix([[1,1,2,2,2],
[3,1,4,3,3],
[0,4,2,4,0],
[0,0,2,0,0],
[0,0,2,0,0]])
I would like to insert a 0 row that displays the amount of row entries in each column.
This was my original code:
A = matrix([[1,1,2,2,2],
[3,1,4,3,3],
[0,4,2,4,0],
[0,0,2,0,0],
[0,0,2,0,0]])
puzzle = A.insert_row(0, sum(A)) Whats wrong with this code is that it gives me the sum of each column, when I just need the count of each column.
What I have
[ 4 6 12 9 5]
[ 1 1 2 2 2]
[ 3 1 4 3 3]
[ 0 4 2 4 0]
[ 0 0 2 0 0]
[ 0 0 2 0 0]
Desired
[ 2 3 5 3 2]
[ 1 1 2 2 2]
[ 3 1 4 3 3]
[ 0 4 2 4 0]
[ 0 0 2 0 0]
[ 0 0 2 0 0]
See also similar question at http://stackoverflow.com/questions/40499228/how-to-create-a-row-that-displays-the-counts-of-column-entries-in-a-matrix-using.