Binaryworld - CComplexNumber - A class for dealing with complex numbers ... [ VB -> Math ]

Option Explicit

'------------------------------------------
' A class for dealing with complex numbers
'------------------------------------------

' The main properties
Public Real As Double
Public Imaginary As Double

' Initialize this complex number
' (returns Me)

Function Init(Real As Double, Imaginary As Double) As CComplexNumber
  Me.Real = Real
  Me.Imaginary = Imaginary
  Set Init = Me
End Function

' Returns another complex number with given
' real and imaginary parts

Function Complex(Real As Double, Imaginary As Double) As CComplexNumber
  Set Complex = New CComplexNumber
  Complex.Real = Real
  Complex.Imaginary = Imaginary
End Function

' Add a complex number to the current one
' (returns Me)

Function Add(other As CComplexNumber) As CComplexNumber
  Real = Real + other.Real
  Imaginary = Imaginary + other.Imaginary
  Set Add = Me
End Function

' Add a complex number to the current one
' (returns the result CComplexNumber)

Function Add2(Real As Double, Imaginary As Double) As CComplexNumber
  Set Add2 = New CComplexNumber
  Add2.Real = Me.Real + Real
  Add2.Imaginary = Me.Imaginary + Imaginary
End Function

' Subtract a complex number from the current one
' (returns the result CComplexNumber)

Function Subtract2(Real As Double, Imaginary As Double) As CComplexNumber
  Set Subtract2 = New CComplexNumber
  Subtract2.Real = Me.Real - Real
  Subtract2.Imaginary = Me.Imaginary - Imaginary
End Function

' Multiple a complex number by the current one
' (returns the result CComplexNumber)

Function Multiply2(Real As Double, Imaginary As Double) As CComplexNumber
  Set Multiply2 = New CComplexNumber
  Multiply2.Real = (Me.Real * Real - Me.Imaginary * Imaginary)
  Multiply2.Imaginary = Me.Real * Imaginary + Me.Imaginary * Real
End Function

' Divide the current number by another complex number
' (returns the result CComplexNumber)

Function Divide2(Real As Double, Imaginary As Double) As CComplexNumber
  Set Divide2 = New CComplexNumber
  Dim sum As Double
  ' create the sum only once
  sum = Real * Real + Imaginary * Imaginary
  ' evaluate the real and imaginary parts
  Divide2.Real = (Me.Real * Real + Me.Imaginary * Imaginary) / sum
  Divide2.Imaginary = (Me.Imaginary * Real - Me.Real * Imaginary) / sum
End Function

' Return the textual description of a complex number

Function Text() As String
  If Imaginary = 0 Then
    Text = LTrim$(Real)
  ElseIf Real = 0 Then
    Text = LTrim$(Imaginary) & "i"
  ElseIf Imaginary > 0 Then
    Text = LTrim$(Real) & "+" & LTrim$(Imaginary) & "i"
  Else
    Text = LTrim$(Real) & LTrim$(Imaginary) & "i"
  End If
End Function