TheAlgorithms/Python · error · ValueError

Each row in the matrix must have exactly {size} characters.

Error message

Each row in the matrix must have exactly {size} characters.

What it means

Error "Each row in the matrix must have exactly {size} characters." thrown in TheAlgorithms/Python.

Source

Thrown at matrix/matrix_based_game.py:87

    Traceback (most recent call last):
        ...
    ValueError: The matrix dont match with size.
    >>> validate_matrix_content(['aa%', 'aaa', 'aaa'], 3)
    Traceback (most recent call last):
        ...
    ValueError: Matrix rows can only contain letters and numbers.
    >>> validate_matrix_content(['aaa', 'aaa', 'aaaa'], 3)
    Traceback (most recent call last):
        ...
    ValueError: Each row in the matrix must have exactly 3 characters.
    """
    print(matrix)
    if len(matrix) != size:
        raise ValueError("The matrix dont match with size.")
    for row in matrix:
        if len(row) != size:
            msg = f"Each row in the matrix must have exactly {size} characters."
            raise ValueError(msg)
        if not all(char.isalnum() for char in row):
            raise ValueError("Matrix rows can only contain letters and numbers.")


def validate_moves(moves: list[tuple[int, int]], size: int) -> None:
    """
    >>> validate_moves([(1, 2), (-1, 0)], 3)
    Traceback (most recent call last):
        ...
    ValueError: Move is out of bounds for a matrix.
    """
    for move in moves:
        x, y = move
        if not (0 <= x < size and 0 <= y < size):
            raise ValueError("Move is out of bounds for a matrix.")


def parse_moves(input_str: str) -> list[tuple[int, int]]:

View on GitHub (pinned to f5988cc097)

Solutions

1. Make every row string exactly 'size' characters long.

When it happens

Trigger: Thrown at matrix/matrix_based_game.py:87 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/a5ed87c633f81185. Report an issue: GitHub.