VB.NET 多项式拟合

以下是VB.NET多项式拟合的示例代码：

' 多项式拟合函数
Public Sub Polyfit(ByVal X() As Double, ByVal Y() As Double, ByVal n As Integer, ByVal m As Integer, ByRef a() As Double)
    Dim i, j, k As Integer
    Dim s As Double
    Dim t() As Double
    ReDim t((m * 2) - 1)
    ReDim a(m - 1)
    For i = 0 To (m * 2) - 1
        s = 0
        For j = 0 To n - 1
            s = s + (X(j) ^ i)
        Next j
        t(i) = s
    Next i
    For i = 0 To m - 1
        s = 0
        For j = 0 To n - 1
            s = s + (X(j) ^ i) * Y(j)
        Next j
        a(i) = s
    Next i
    For k = 0 To m - 1
        For i = k To (m * 2) - 1
            a(i) = a(i) / t(i - k)
        Next i
        For i = k + 1 To m - 1
            s = a(i)
            For j = k To i - 1
                s = s - a(j) * t(i - j + k)
            Next j
            a(i) = s
        Next i
    Next k
End Sub

以上代码实现了多项式拟合函数，其中X()和Y()分别为输入的数据点的横纵坐标数组，n为数据点的个数，m为拟合多项式的次数，a()为返回的拟合多项式的系数数组。