如何在给定矩阵中找到所有大于阈值的子矩阵值(不使用numpy和Scipy)

def calculate_submatrix_sum(matrix, top_left, bottom_right):
    sum = 0
    for i in range(top_left[0], bottom_right[0] + 1):
        for j in range(top_left[1], bottom_right[1] + 1):
            sum += matrix[i][j]
    return sum

def find_submatrix_values(matrix, threshold):
    result = []
    rows = len(matrix)
    cols = len(matrix[0])
    for i in range(rows):
        for j in range(cols):
            for k in range(i, rows):
                for l in range(j, cols):
                    submatrix_sum = calculate_submatrix_sum(matrix, (i, j), (k, l))
                    if submatrix_sum > threshold:
                        result.append(submatrix_sum)
    return result

# 示例用法
matrix = [
    [1, 2, 3],
    [4, 5, 6],
    [7, 8, 9]
]
threshold = 15
submatrix_values = find_submatrix_values(matrix, threshold)
print(submatrix_values)