nlmivmainmodule.bas

来自「科学与工程数值计算算法（Visual Basic版）一书的源代码。对科学研究者自」· BAS 代码 · 共 47 行

Attribute VB_Name = "MainModule"
Sub Main()
    Dim n As Integer, m As Integer
    Dim s As String
    
    ' 3个未知数
    m = 3
    ' 2次方程
    n = 2
    
    ' 分配初值和解的内存
    ReDim x(n) As Double
    
    ' 初值数组
    x(1) = 1
    x(2) = -1
    
    '求解
    If NLMiv(m, n, x, 0.000001, 0.000001, 4) Then
        s = ""
        For i = 1 To n
            s = s & "x(" & i & ") = " & x(i) & Chr(13)
        Next i
        
        MsgBox "求解成功！" & Chr(13) & Chr(13) & s
    Else
        MsgBox "求解失败"
    End If
    
End Sub

Sub Func(x() As Double, y() As Double)
    y(1) = x(1) * x(1) + 7# * x(1) * x(2) + 3# * x(2) * x(2) + 0.5
    y(2) = x(1) * x(1) - 2# * x(1) * x(2) + x(2) * x(2) - 1#
    y(3) = x(1) + x(2) + 1#
End Sub

Sub FuncMJ(x() As Double, p() As Double)
    p(1, 1) = 2# * x(1) + 7# * x(2)
    p(1, 2) = 7# * x(1) + 6# * x(2)
    p(2, 1) = 2# * x(1) - 2# * x(2)
    p(2, 2) = -2# * x(1) + 2# * x(2)
    p(3, 1) = 1#
    p(3, 2) = 1#
End Sub