numpy subtract matrix code example
Example 1: python numpy array subtract
array1=numpy.array([1.1, 2.2, 3.3])
array2=numpy.array([1, 2, 3])
difference = array1 - array2
Example 2: how to subtract two matrices in python
matrix1 = [[0, 1, 2],
[3, 5, 5],
[6, 7, 8]]
matrix2 = [[1, 2, 3],
[4, 5, 6],
[7, 8, 9]]
#output = [[-1, -1, -1],
# [-1, 0, -1],
# [-1, -1, -1]]
def subtractTheMatrix(matrix1, matrix2):
matrix1Rows = len(matrix1)
matrix2Rows = len(matrix2)
matrix1Col = len(matrix1[0])
matrix2Col = len(matrix2[0])
#base case
if(matrix1Rows != matrix2Rows or matrix1Col != matrix2Col):
return "ERROR: dimensions of the two arrays must be the same"
#make a matrix of the same size as matrix 1 and matrix 2
matrix = []
rows = []
for i in range(0, matrix1Rows):
for j in range(0, matrix2Col):
rows.append(0)
matrix.append(rows.copy())
rows = []
#loop through the two matricies and the subtraction should be placed in the
#matrix
for i in range(0, matrix1Rows):
for j in range(0, matrix2Col):
matrix[i][j] = matrix1[i][j] - matrix2[i][j]
return matrix
print(subtractTheMatrix(matrix1, matrix2))