by Tim Markoski (6 Submissions)
Category: Math/Dates
Compatability: Visual Basic 3.0
Difficulty: Beginner
Date Added: Wed 3rd February 2021
Rating: 
(7 Votes)
Simplifies the use of the most common Trig Functions (Sine, Cosine, Tangent) and their Inverse Functions (ArcSine, ArcCosine, ArcTangent).
The native VB Trig functions require the conversion from degrees to radians or vice-versa.
These functions eliminate that need.
VBcodersAttribute VB_Name = "TRIGONOMETRY"
Option Explicit
Public Function Sine(p_dblVal As Double) As Double
' Comments :
' Parameters: p_dblVal -
' Returns : Double -
' Modified :
'
' -------------------------
'Degree Input Radian Output
On Error GoTo PROC_ERR
Dim dblPi As Double
Dim dblRadian As Double
' xx Calculate the value of Pi.
dblPi = 4 * Atn(1)
' xx To convert degrees to radians,
' multiply degrees by Pi / 180.
dblRadian = dblPi / 180
p_dblVal = Val(p_dblVal * dblRadian)
Sine = Sin(p_dblVal)
PROC_EXIT:
Exit Function
PROC_ERR:
Sine = 0
MsgBox Err.Description, vbExclamation
Resume PROC_EXIT
End Function
Public Function Cosine(p_dblVal As Double) As Double
' Comments :
' Parameters: p_dblVal -
' Returns : Double -
' Modified :
'
' -------------------------
'Degree Input Radian Output
On Error GoTo PROC_ERR
Dim dblPi As Double
Dim dblRadian As Double
' xx Calculate the value of Pi.
dblPi = 4 * Atn(1)
' xx To convert degrees to radians,
' multiply degrees by Pi / 180.
dblRadian = dblPi / 180
p_dblVal = Val(p_dblVal * dblRadian)
Cosine = Cos(p_dblVal)
PROC_EXIT:
Exit Function
PROC_ERR:
Cosine = 0
MsgBox Err.Description, vbExclamation
Resume PROC_EXIT
End Function
Public Function Tangent(p_dblVal As Double) As Double
' Comments :
' Parameters: p_dblVal -
' Returns : Double -
' Modified :
'
' -------------------------
'Degree Input Radian Output
On Error GoTo PROC_ERR
Dim dblPi As Double
Dim dblRadian As Double
' xx Calculate the value of Pi.
dblPi = 4 * Atn(1)
' xx To convert degrees to radians,
' multiply degrees by Pi / 180.
dblRadian = dblPi / 180
p_dblVal = Val(p_dblVal * dblRadian)
Tangent = Tan(p_dblVal)
PROC_EXIT:
Exit Function
PROC_ERR:
Tangent = 0
MsgBox Err.Description, vbExclamation
Resume PROC_EXIT
End Function
Public Function ArcSine(p_dblVal As Double) As Double
' Comments :
' Parameters: p_dblVal -
' Returns : Double -
' Modified :
'
' -------------------------
'Radian Input Degree Output
On Error GoTo PROC_ERR
Dim dblSqr As Double
Dim dblPi As Double
Dim dblDegree As Double
' xx Calculate the value of Pi.
dblPi = 4 * Atn(1)
' xx To convert radians to degrees,
' multiply radians by 180/pi.
dblDegree = 180 / dblPi
p_dblVal = Val(p_dblVal)
dblSqr = Sqr(-p_dblVal * p_dblVal + 1)
' xx Prevent division by Zero error
If dblSqr = 0 Then
dblSqr = 1E-30
End If
ArcSine = Atn(p_dblVal / dblSqr) * dblDegree
PROC_EXIT:
Exit Function
PROC_ERR:
ArcSine = 0
MsgBox Err.Description, vbExclamation
Resume PROC_EXIT
End Function
Public Function ArcCosine(p_dblVal As Double) As Double
' Comments :
' Parameters: p_dblVal -
' Returns : Double -
' Modified :
'
' -------------------------
'Radian Input Degree Output
On Error GoTo PROC_ERR
Dim dblSqr As Double
Dim dblPi As Double
Dim dblDegree As Double
' xx Calculate the value of Pi.
dblPi = 4 * Atn(1)
' xx To convert radians to degrees,
' multiply radians by 180/pi.
dblDegree = 180 / dblPi
p_dblVal = Val(p_dblVal)
dblSqr = Sqr(-p_dblVal * p_dblVal + 1)
' xx Prevent division by Zero error
If dblSqr = 0 Then
dblSqr = 1E-30
End If
ArcCosine = (Atn(-p_dblVal / dblSqr) + 2 * Atn(1)) * dblDegree
PROC_EXIT:
Exit Function
PROC_ERR:
ArcCosine = 0
MsgBox Err.Description, vbExclamation
Resume PROC_EXIT
End Function
Public Function ArcTangent(p_dblVal As Double) As Double
' Comments :
' Parameters: p_dblVal -
' Returns : Double -
' Modified :
'
' -------------------------
'Radian Input Degree Output
On Error GoTo PROC_ERR
Dim dblPi As Double
Dim dblDegree As Double
' xx Calculate the value of Pi.
dblPi = 4 * Atn(1)
' xx To convert radians to degrees,
' multiply radians by 180/pi.
dblDegree = 180 / dblPi
p_dblVal = Val(p_dblVal)
ArcTangent = Atn(p_dblVal) * dblDegree
PROC_EXIT:
Exit Function
PROC_ERR:
ArcTangent = 0
MsgBox Err.Description, vbExclamation
Resume PROC_EXIT
End Function