追赶法解三对角矩阵Python实现

以下是用追赶法解三对角矩阵的 Python 代码：

def tridiagonal_solver(A, B, C, R):
    """
    Solve the tridiagonal system Ax = R using the Thomas algorithm
    where A, B, and C are the diagonal and off-diagonal elements of a tridiagonal matrix
    R is the right-hand side, and X is the solution vector
    """
    n = len(R)
    M = [0] * n  # temporary storage

    # Forward elimination
    M[0] = B[0] / A[0]
    for i in range(1, n-1):
        M[i] = B[i] / (A[i] - M[i-1] * C[i-1])

    # Back substitution
    X = [0] * n
    X[-1] = (R[-1] - C[-1] * X[-2]) / (A[-1] - C[-1] * M[-2])
    for i in range(n-2, 0, -1):
        X[i] = M[i] * X[i+1] + (R[i] - C[i] * X[i+1]) / A[i]
    X[0] = (R[0] - C[0] * X[1]) / A[0]

    return X

这个代码和 Fortran 版本非常相似，使用了同样的 Thomas 算法来解三对角线性方程组。在这个代码中，首先进行了前向消元，然后进行了回带代入，最终得到了方程组的解X。需要注意的是，在 Python 中，我们需要使用列表来代替数组，并且需要在函数定义中指定参数类型。