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# 11.6 (Algebra: multiply two matrices) Write a function to multiply two matrices. The
# header of the function is:
# def multiplyMatrix(a, b)
# To multiply matrix a by matrix b, the number of columns in a must be the same as
# the number of rows in b, and the two matrices must have elements of the same or
# compatible types. Let c be the result of the multiplication. Assume the column size
# of matrix a is n. Each element cij is For
# example, ai1 * b1j + ai2 * b2j + c cij + ain * bnj for two matrices a and b, c is
# where cij = ai1 * b1j + ai2 * b2j + ai3 * b3j. Write a test program that prompts the user to enter two matrices and displays
# their product.
import math
def multiplyMatrix(a, b):
list = len(m2[0]) * [0]
result = []
for i in range(len(m1)):
result.append([x for x in list])
for i in range(len(result)):
for j in range(len(result[0])):
for k in range(len(m2)):
result[i][j] += m1[i][k] * m2[k][j]
return result
l1 = input("Enter matrix 1: ").split()
l2 = input("Enter matrix 2: ").split()
# shape the input into a 3*3 matrix
m1 = []
m2 = []
counter = 0
size = int(math.sqrt(len(l1)))
for i in range(size):
m1.append([0] * size)
m2.append([0] * size)
for j in range(size):
m1[i][j] = float(l1[counter])
m2[i][j] = float(l2[counter])
counter += 1
res = multiplyMatrix(m1, m2)
res = [["%.1f" % x for x in member] for member in res] # format values
for i in range(size):
print(m1[i], end=' ')
if i == 1:
print(' *', end='')
print(' ', end='')
else:
print('\t', end='')
print(m2[i], end=' ')
if i == 1:
print(' =', end='')
print(' ', end='')
else:
print('\t', end='')
print(res[i], end=' ')
print()
