Add error & test checks for matrix_operations.py (#925)

* Update matrix_operation.py

1. Adding error checks for integer inputs
2. Adding error checks for matrix operations where size requirements do not match up
3. Added matrix subtraction function
4. included error check so only integer is passed into identity function

* Create test_matrix_operation.py

* Update matrix_ops and Add Test Cases

1. Included error checks in matrix operation.  There were some cases where the functions would not work correctly.

2. PEP8 changes to matrix_operations.py

3. added test cases for matrix operations using pytest.

* Update pytest.ini

Add carriage return to end of file
This commit is contained in:
Stephen Gemin 2019-07-19 23:06:29 -04:00 committed by Christian Clauss
parent dc1de946ea
commit 4e0717c3cf
3 changed files with 216 additions and 33 deletions

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@ -1,64 +1,131 @@
from __future__ import print_function
"""
function based version of matrix operations, which are just 2D arrays
"""
def add(matrix_a, matrix_b):
rows = len(matrix_a)
columns = len(matrix_a[0])
matrix_c = []
for i in range(rows):
list_1 = []
for j in range(columns):
val = matrix_a[i][j] + matrix_b[i][j]
list_1.append(val)
matrix_c.append(list_1)
return matrix_c
if _check_not_integer(matrix_a) and _check_not_integer(matrix_b):
rows, cols = _verify_matrix_sizes(matrix_a, matrix_b)
matrix_c = []
for i in range(rows[0]):
list_1 = []
for j in range(cols[0]):
val = matrix_a[i][j] + matrix_b[i][j]
list_1.append(val)
matrix_c.append(list_1)
return matrix_c
def scalarMultiply(matrix , n):
def subtract(matrix_a, matrix_b):
if _check_not_integer(matrix_a) and _check_not_integer(matrix_b):
rows, cols = _verify_matrix_sizes(matrix_a, matrix_b)
matrix_c = []
for i in range(rows[0]):
list_1 = []
for j in range(cols[0]):
val = matrix_a[i][j] - matrix_b[i][j]
list_1.append(val)
matrix_c.append(list_1)
return matrix_c
def scalar_multiply(matrix, n):
return [[x * n for x in row] for row in matrix]
def multiply(matrix_a, matrix_b):
matrix_c = []
n = len(matrix_a)
for i in range(n):
list_1 = []
for j in range(n):
val = 0
for k in range(n):
val = val + matrix_a[i][k] * matrix_b[k][j]
list_1.append(val)
matrix_c.append(list_1)
return matrix_c
if _check_not_integer(matrix_a) and _check_not_integer(matrix_b):
matrix_c = []
rows, cols = _verify_matrix_sizes(matrix_a, matrix_b)
if cols[0] != rows[1]:
raise ValueError(f'Cannot multiply matrix of dimensions ({rows[0]},{cols[0]}) '
f'and ({rows[1]},{cols[1]})')
for i in range(rows[0]):
list_1 = []
for j in range(cols[1]):
val = 0
for k in range(cols[1]):
val = val + matrix_a[i][k] * matrix_b[k][j]
list_1.append(val)
matrix_c.append(list_1)
return matrix_c
def identity(n):
"""
:param n: dimension for nxn matrix
:type n: int
:return: Identity matrix of shape [n, n]
"""
n = int(n)
return [[int(row == column) for column in range(n)] for row in range(n)]
def transpose(matrix):
return map(list , zip(*matrix))
def transpose(matrix, return_map=True):
if _check_not_integer(matrix):
if return_map:
return map(list, zip(*matrix))
else:
# mt = []
# for i in range(len(matrix[0])):
# mt.append([row[i] for row in matrix])
# return mt
return [[row[i] for row in matrix] for i in range(len(matrix[0]))]
def minor(matrix, row, column):
minor = matrix[:row] + matrix[row + 1:]
minor = [row[:column] + row[column + 1:] for row in minor]
return minor
def determinant(matrix):
if len(matrix) == 1: return matrix[0][0]
if len(matrix) == 1:
return matrix[0][0]
res = 0
for x in range(len(matrix)):
res += matrix[0][x] * determinant(minor(matrix , 0 , x)) * (-1) ** x
res += matrix[0][x] * determinant(minor(matrix, 0, x)) * (-1) ** x
return res
def inverse(matrix):
det = determinant(matrix)
if det == 0: return None
if det == 0:
return None
matrixMinor = [[] for _ in range(len(matrix))]
matrix_minor = [[] for _ in range(len(matrix))]
for i in range(len(matrix)):
for j in range(len(matrix)):
matrixMinor[i].append(determinant(minor(matrix , i , j)))
matrix_minor[i].append(determinant(minor(matrix, i, j)))
cofactors = [[x * (-1) ** (row + col) for col, x in enumerate(matrixMinor[row])] for row in range(len(matrix))]
cofactors = [[x * (-1) ** (row + col) for col, x in enumerate(matrix_minor[row])] for row in range(len(matrix))]
adjugate = transpose(cofactors)
return scalarMultiply(adjugate , 1/det)
return scalar_multiply(adjugate, 1/det)
def _check_not_integer(matrix):
try:
rows = len(matrix)
cols = len(matrix[0])
return True
except TypeError:
raise TypeError("Cannot input an integer value, it must be a matrix")
def _shape(matrix):
return list((len(matrix), len(matrix[0])))
def _verify_matrix_sizes(matrix_a, matrix_b):
shape = _shape(matrix_a)
shape += _shape(matrix_b)
if shape[0] != shape[2] or shape[1] != shape[3]:
raise ValueError(f"operands could not be broadcast together with shape "
f"({shape[0], shape[1]}), ({shape[2], shape[3]})")
return [shape[0], shape[2]], [shape[1], shape[3]]
def main():
matrix_a = [[12, 10], [3, 9]]
@ -68,9 +135,10 @@ def main():
print('Add Operation, %s + %s = %s \n' %(matrix_a, matrix_b, (add(matrix_a, matrix_b))))
print('Multiply Operation, %s * %s = %s \n' %(matrix_a, matrix_b, multiply(matrix_a, matrix_b)))
print('Identity: %s \n' %identity(5))
print('Minor of %s = %s \n' %(matrix_c, minor(matrix_c , 1 , 2)))
print('Minor of %s = %s \n' %(matrix_c, minor(matrix_c, 1, 2)))
print('Determinant of %s = %s \n' %(matrix_b, determinant(matrix_b)))
print('Inverse of %s = %s\n'%(matrix_d, inverse(matrix_d)))
if __name__ == '__main__':
main()

3
matrix/tests/pytest.ini Normal file
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@ -0,0 +1,3 @@
[pytest]
markers =
mat_ops: tests for matrix operations

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"""
Testing here assumes that numpy and linalg is ALWAYS correct!!!!
If running from PyCharm you can place the following line in "Additional Arguments" for the pytest run configuration
-vv -m mat_ops -p no:cacheprovider
"""
# standard libraries
import sys
import numpy as np
import pytest
import logging
# Custom/local libraries
from matrix import matrix_operation as matop
mat_a = [[12, 10], [3, 9]]
mat_b = [[3, 4], [7, 4]]
mat_c = [[3, 0, 2], [2, 0, -2], [0, 1, 1]]
mat_d = [[3, 0, -2], [2, 0, 2], [0, 1, 1]]
mat_e = [[3, 0, 2], [2, 0, -2], [0, 1, 1], [2, 0, -2]]
mat_f = [1]
mat_h = [2]
logger = logging.getLogger()
logger.level = logging.DEBUG
stream_handler = logging.StreamHandler(sys.stdout)
logger.addHandler(stream_handler)
@pytest.mark.mat_ops
@pytest.mark.parametrize(('mat1', 'mat2'), [(mat_a, mat_b), (mat_c, mat_d), (mat_d, mat_e),
(mat_f, mat_h)])
def test_addition(mat1, mat2):
if (np.array(mat1)).shape < (2, 2) or (np.array(mat2)).shape < (2, 2):
with pytest.raises(TypeError):
logger.info(f"\n\t{test_addition.__name__} returned integer")
matop.add(mat1, mat2)
elif (np.array(mat1)).shape == (np.array(mat2)).shape:
logger.info(f"\n\t{test_addition.__name__} with same matrix dims")
act = (np.array(mat1) + np.array(mat2)).tolist()
theo = matop.add(mat1, mat2)
assert theo == act
else:
with pytest.raises(ValueError):
logger.info(f"\n\t{test_addition.__name__} with different matrix dims")
matop.add(mat1, mat2)
@pytest.mark.mat_ops
@pytest.mark.parametrize(('mat1', 'mat2'), [(mat_a, mat_b), (mat_c, mat_d), (mat_d, mat_e),
(mat_f, mat_h)])
def test_subtraction(mat1, mat2):
if (np.array(mat1)).shape < (2, 2) or (np.array(mat2)).shape < (2, 2):
with pytest.raises(TypeError):
logger.info(f"\n\t{test_subtraction.__name__} returned integer")
matop.subtract(mat1, mat2)
elif (np.array(mat1)).shape == (np.array(mat2)).shape:
logger.info(f"\n\t{test_subtraction.__name__} with same matrix dims")
act = (np.array(mat1) - np.array(mat2)).tolist()
theo = matop.subtract(mat1, mat2)
assert theo == act
else:
with pytest.raises(ValueError):
logger.info(f"\n\t{test_subtraction.__name__} with different matrix dims")
assert matop.subtract(mat1, mat2)
@pytest.mark.mat_ops
@pytest.mark.parametrize(('mat1', 'mat2'), [(mat_a, mat_b), (mat_c, mat_d), (mat_d, mat_e),
(mat_f, mat_h)])
def test_multiplication(mat1, mat2):
if (np.array(mat1)).shape < (2, 2) or (np.array(mat2)).shape < (2, 2):
logger.info(f"\n\t{test_multiplication.__name__} returned integer")
with pytest.raises(TypeError):
matop.add(mat1, mat2)
elif (np.array(mat1)).shape == (np.array(mat2)).shape:
logger.info(f"\n\t{test_multiplication.__name__} meets dim requirements")
act = (np.matmul(mat1, mat2)).tolist()
theo = matop.multiply(mat1, mat2)
assert theo == act
else:
with pytest.raises(ValueError):
logger.info(f"\n\t{test_multiplication.__name__} does not meet dim requirements")
assert matop.subtract(mat1, mat2)
@pytest.mark.mat_ops
def test_scalar_multiply():
act = (3.5 * np.array(mat_a)).tolist()
theo = matop.scalar_multiply(mat_a, 3.5)
assert theo == act
@pytest.mark.mat_ops
def test_identity():
act = (np.identity(5)).tolist()
theo = matop.identity(5)
assert theo == act
@pytest.mark.mat_ops
@pytest.mark.parametrize('mat', [mat_a, mat_b, mat_c, mat_d, mat_e, mat_f])
def test_transpose(mat):
if (np.array(mat)).shape < (2, 2):
with pytest.raises(TypeError):
logger.info(f"\n\t{test_transpose.__name__} returned integer")
matop.transpose(mat)
else:
act = (np.transpose(mat)).tolist()
theo = matop.transpose(mat, return_map=False)
assert theo == act