方位角.frm

采用vb程序语言编写

VERSION 5.00
Begin VB.Form Form1 
   Caption         =   "Form1"
   ClientHeight    =   5415
   ClientLeft      =   60
   ClientTop       =   450
   ClientWidth     =   7455
   ForeColor       =   &H000000FF&
   LinkTopic       =   "Form1"
   ScaleHeight     =   5415
   ScaleWidth      =   7455
   StartUpPosition =   3  '窗口缺省
   Begin VB.TextBox Text5 
      ForeColor       =   &H000000FF&
      Height          =   735
      Left            =   3120
      Locked          =   -1  'True
      TabIndex        =   5
      Top             =   2520
      Width           =   2295
   End
   Begin VB.TextBox Text4 
      Height          =   495
      Left            =   4800
      TabIndex        =   4
      Top             =   1440
      Width           =   1575
   End
   Begin VB.TextBox Text3 
      Height          =   615
      Left            =   1200
      TabIndex        =   3
      Top             =   1080
      Width           =   1335
   End
   Begin VB.TextBox Text2 
      Height          =   615
      Left            =   4800
      TabIndex        =   2
      Top             =   360
      Width           =   1455
   End
   Begin VB.TextBox Text1 
      Height          =   495
      Left            =   1080
      TabIndex        =   1
      Top             =   240
      Width           =   1335
   End
   Begin VB.CommandButton Command1 
      Caption         =   "方位角计算"
      Height          =   735
      Left            =   2160
      TabIndex        =   0
      Top             =   3960
      Width           =   2055
   End
   Begin VB.Label Label5 
      Caption         =   "MN方位角输出："
      Height          =   555
      Left            =   1320
      TabIndex        =   10
      Top             =   2640
      Width           =   1575
   End
   Begin VB.Label Label4 
      Caption         =   "ym："
      Height          =   375
      Left            =   4080
      TabIndex        =   9
      Top             =   1560
      Width           =   495
   End
   Begin VB.Label Label3 
      Caption         =   "xm："
      Height          =   255
      Left            =   480
      TabIndex        =   8
      Top             =   1320
      Width           =   615
   End
   Begin VB.Label Label2 
      Caption         =   "yn："
      Height          =   255
      Left            =   4080
      TabIndex        =   7
      Top             =   480
      Width           =   615
   End
   Begin VB.Label Label1 
      Caption         =   "xn："
      Height          =   255
      Left            =   480
      TabIndex        =   6
      Top             =   360
      Width           =   615
   End
End
Attribute VB_Name = "Form1"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Option Explicit
'Dim a As Double

Private Sub Command1_Click()
    Dim a1 As Double, a2 As Double, a3 As Double, a4 As Double
    Dim b
    a1 = Val(Text1.Text)
    a2 = Val(Text2.Text)
    a3 = Val(Text3.Text)
    a4 = Val(Text4.Text)
    If a1 = 0 Or a2 = 0 Or a3 = 0 Or a4 = 0 Then  '假若参数输入不全，不计算
    Command1.Enabled = False
    Exit Sub
    End If
    b = Qfangweijiao(a1, a2, a3, a4)
    
    Text5.Text = Format(b, "###.0000")
    'Text5.Text = Str(b)
End Sub

Function Qfangweijiao(xn As Double, yn As Double, xm As Double, ym As Double) As Double
    Dim c As Double, d As Double
    c = gn(xn, xm)
    Const PI = 3.1415926
  
    If yn - ym = 0 And yn < 0 Then
    yn = ym - 0.00000001
    Qfangweijiao = 180
    ElseIf yn - ym = 0 And yn > 0 Then
    yn = ym + 0.00000001
    Qfangweijiao = 90
    Else
    Qfangweijiao = Atn((xn - xm) / (yn - ym)) * 180 / PI + 180 * c '改进模式只在yn<>ym时成立，yn=ym时需单独考虑
    End If
End Function


Function gn(r1 As Double, r2 As Double)  ' 取符号函数
    If r1 - r2 > 0 Then
        gn = 2
      ElseIf r1 - r2 < 0 Then
       gn = 1
     End If
 End Function