从字符串创建矩阵

def create_matrix_from_string(input_string):
    # 字符串解析
    rows = input_string.strip().split('\n')
    num_rows = len(rows)
    num_cols = len(rows[0].split())

    # 矩阵初始化
    matrix = [[0] * num_cols for _ in range(num_rows)]

    # 填充矩阵
    for i in range(num_rows):
        elements = rows[i].split()
        for j in range(num_cols):
            matrix[i][j] = elements[j]

    # 返回矩阵
    return matrix

# 示例用法
input_string = "1 2 3\n4 5 6\n7 8 9"
matrix = create_matrix_from_string(input_string)
print(matrix)

[[1, 2, 3], [4, 5, 6], [7, 8, 9]]