Python 3- matrix input

Question

The program i wrote a program so that main calls the following functions:

getMatrix – creates and returns a 3 x 3 matrix

printMatrix – prints the matrix row by row

sumRow – returns the sum of the elements of a single row of the matrix (pass in the matrix and the row index)

The problem i am facing is that it is asking for the input twice, instead of once.

def getMatrix():
   matrix = []
   numberOfRows = eval(input("Enter the number of rows: "))
   numberOfColumns = eval(input("Enter number of columns: "))
   for row in range(numberOfRows):
      matrix.append([])
      for column in range(numberOfColumns):
         value = eval(input("Enter an element and press enter: "))
         matrix[row].append(value)
   return matrix

# Print 2 dimensional list
def printMatrix(matrix):
   matrix = getMatrix()
   for row in range(len(matrix)):
      for column in range(len(matrix[row])):
         print(matrix[row][column], end = " ")
      print()

# Add each element in row to total 
def sumRow(matrix):
   for row in range(len(matrix[0])):
      total = 0
      for column in range(len(matrix)):
         total += matrix[row][column]
      print("Sum for matrix", row, "is", total)

def main():
   matrix = getMatrix()
   printMatrix(matrix)
   total = sumRow(matrix)
main()

Answer 1

In main:

matrix = getMatrix()
printMatrix(matrix)

In printMatrix:

matrix = getMatrix()

Which immediately masks the matrix argument you passed in, by the way.

In getMatrix:

matrix = []
numberOfRows = eval(input("Enter the number of rows: "))
numberOfColumns = eval(input("Enter number of columns: "))

You should be using int(), by the way, not eval().

So there are two calls to getMatrix(), which means two requests for input. Remove matrix = getMatrix() from printMatrix. That's not what that function is supposed to be doing, anyway.