TheAlgorithms/Python · error · ValueError
Subtraction requires matrices of the same order
Error message
Subtraction requires matrices of the same order
What it means
Error "Subtraction requires matrices of the same order" thrown in TheAlgorithms/Python.
Source
Thrown at matrix/matrix_class.py:310
def __ne__(self, other: object) -> bool:
return not self == other
def __neg__(self) -> Matrix:
return self * -1
def __add__(self, other: Matrix) -> Matrix:
if self.order != other.order:
raise ValueError("Addition requires matrices of the same order")
return Matrix(
[
[self.rows[i][j] + other.rows[i][j] for j in range(self.num_columns)]
for i in range(self.num_rows)
]
)
def __sub__(self, other: Matrix) -> Matrix:
if self.order != other.order:
raise ValueError("Subtraction requires matrices of the same order")
return Matrix(
[
[self.rows[i][j] - other.rows[i][j] for j in range(self.num_columns)]
for i in range(self.num_rows)
]
)
def __mul__(self, other: Matrix | float) -> Matrix:
if isinstance(other, (int, float)):
return Matrix(
[[int(element * other) for element in row] for row in self.rows]
)
elif isinstance(other, Matrix):
if self.num_columns != other.num_rows:
raise ValueError(
"The number of columns in the first matrix must "
"be equal to the number of rows in the second"
)View on GitHub (pinned to f5988cc097)
Solutions
- Subtract only matrices with identical dimensions.
When it happens
Trigger: Thrown at matrix/matrix_class.py:310 when the library encounters an invalid state.
Common situations: See trigger scenarios.
AI-assisted analysis of TheAlgorithms/Python@f5988cc097 (2026-08-14).
Data as JSON: /api/errors/4b1c54ceb04f4bbe.
Report an issue: GitHub.