Math Functions (Visual Basic)
The math functions in Visual Basic 6 have been replaced by equivalent methods in the System.Math class of the .NET Framework.
The .NET Framework math methods are functionally identical to their Visual Basic 6 counterparts, although some have slightly different names. For example, the .NET Framework equivalent of the Visual Basic 6 Atn function is Atan. The following table lists the Visual Basic 6 math function names and the equivalent .NET Framework methods.
| Visual Basic 6 function | .NET Framework method | Description |
|---|---|---|
| Abs | Returns the absolute value of a specified number. | |
| Atn | Atan | Returns a Double value containing the angle whose tangent is the specified number. |
| Cos | Returns a Double value containing the cosine of the specified angle. | |
| Exp | Returns a Double value containing e (the base of natural logarithms) raised to the specified power. | |
| Log | Returns a Double value containing the logarithm of a specified number. This method is overloaded and can return either the natural (base e) logarithm of a specified number or the logarithm of a specified number in a specified base. | |
| Round | Returns a Double value containing the number nearest the specified value. Additional round functions are available as methods of the intrinsic types such as Round. | |
| Sgn | Returns an Integer value indicating the sign of a number. | |
| Sin | Returns a Double value specifying the sine of an angle. | |
| Sqr | Returns a Double value specifying the square root of a number. | |
| Tan | Returns a Double value containing the tangent of an angle. |
In addition, the .NET Framework math class provides constants and other static methods for trigonometric, logarithmic, and other common mathematical functions. All of these can be used in a Visual Basic program.
To use these functions without qualification, import the System.Math namespace into your project by adding the following code to the top of the source code:
'Imports System.Math
This example uses the Abs method of the Math class to compute the absolute value of a number.
' Returns 50.3. Dim MyNumber1 As Double = Math.Abs(50.3) ' Returns 50.3. Dim MyNumber2 As Double = Math.Abs(-50.3)
This example uses the Atan method of the Math class to calculate the value of pi.
Public Function GetPi() As Double
' Calculate the value of pi.
Return 4.0 * Math.Atan(1.0)
End Function
This example uses the Cos method of the Math class to return the cosine of an angle.
Public Function Sec(ByVal angle As Double) As Double
' Calculate the secant of angle, in radians.
Return 1.0 / Math.Cos(angle)
End Function
This example uses the Exp method of the Math class to return e raised to a power.
Public Function Sinh(ByVal angle As Double) As Double
' Calculate hyperbolic sine of an angle, in radians.
Return (Math.Exp(angle) - Math.Exp(-angle)) / 2.0
End Function
This example uses the Log method of the Math class to return the natural logarithm of a number.
Public Function Asinh(ByVal value As Double) As Double
' Calculate inverse hyperbolic sine, in radians.
Return Math.Log(value + Math.Sqrt(value * value + 1.0))
End Function
This example uses the Round method of the Math class to round a number to the nearest integer.
' Returns 3. Dim MyVar2 As Double = Math.Round(2.8)
This example uses the Sign method of the Math class to determine the sign of a number.
' Returns 1. Dim MySign1 As Integer = Math.Sign(12) ' Returns -1. Dim MySign2 As Integer = Math.Sign(-2.4) ' Returns 0. Dim MySign3 As Integer = Math.Sign(0)
This example uses the Sin method of the Math class to return the sine of an angle.
Public Function Csc(ByVal angle As Double) As Double
' Calculate cosecant of an angle, in radians.
Return 1.0 / Math.Sin(angle)
End Function
This example uses the Sqrt method of the Math class to calculate the square root of a number.
' Returns 2. Dim MySqr1 As Double = Math.Sqrt(4) ' Returns 4.79583152331272. Dim MySqr2 As Double = Math.Sqrt(23) ' Returns 0. Dim MySqr3 As Double = Math.Sqrt(0) ' Returns NaN (not a number). Dim MySqr4 As Double = Math.Sqrt(-4)
This example uses the Tan method of the Math class to return the tangent of an angle.
Public Function Ctan(ByVal angle As Double) As Double
' Calculate cotangent of an angle, in radians.
Return 1.0 / Math.Tan(angle)
End Function