Math.PI Field 
Definition
Important
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Represents the ratio of the circumference of a circle to its diameter, specified by the constant, π.
public: double PI = 3.1415926535897931;public const double PI = 3.1415926535897931;val mutable PI : doublePublic Const PI As Double  = 3.1415926535897931Field Value
Value = 3.1415926535897931Examples
The following example uses PI to assist in the computation of the inner angles of a given trapezoid.
/// <summary>
/// The following class represents simple functionality of the trapezoid.
/// </summary>
using System;
namespace MathClassCS
{
    class MathTrapezoidSample
    {
        private double m_longBase;
        private double m_shortBase;
        private double m_leftLeg;
        private double m_rightLeg;
        public MathTrapezoidSample(double longbase, double shortbase, double leftLeg, double rightLeg)
        {
            m_longBase = Math.Abs(longbase);
            m_shortBase = Math.Abs(shortbase);
            m_leftLeg = Math.Abs(leftLeg);
            m_rightLeg = Math.Abs(rightLeg);
        }
        private double GetRightSmallBase()
        {
            return (Math.Pow(m_rightLeg,2.0) - Math.Pow(m_leftLeg,2.0) + Math.Pow(m_longBase,2.0) + Math.Pow(m_shortBase,2.0) - 2* m_shortBase * m_longBase)/ (2*(m_longBase - m_shortBase));
        }
        public double GetHeight()
        {
            double x = GetRightSmallBase();
            return Math.Sqrt(Math.Pow(m_rightLeg,2.0) - Math.Pow(x,2.0));
        }
        public double GetSquare()
        {
            return GetHeight() * m_longBase / 2.0;
        }
        public double GetLeftBaseRadianAngle()
        {
            double sinX = GetHeight()/m_leftLeg;
            return Math.Round(Math.Asin(sinX),2);
        }
        public double GetRightBaseRadianAngle()
        {
            double x = GetRightSmallBase();
            double cosX = (Math.Pow(m_rightLeg,2.0) + Math.Pow(x,2.0) - Math.Pow(GetHeight(),2.0))/(2*x*m_rightLeg);
            return Math.Round(Math.Acos(cosX),2);
        }
        public double GetLeftBaseDegreeAngle()
        {
            double x = GetLeftBaseRadianAngle() * 180/ Math.PI;
            return Math.Round(x,2);
        }
        public double GetRightBaseDegreeAngle()
        {
            double x = GetRightBaseRadianAngle() * 180/ Math.PI;
            return Math.Round(x,2);
        }
        static void Main(string[] args)
        {
            MathTrapezoidSample trpz = new MathTrapezoidSample(20.0, 10.0, 8.0, 6.0);
            Console.WriteLine("The trapezoid's bases are 20.0 and 10.0, the trapezoid's legs are 8.0 and 6.0");
            double h = trpz.GetHeight();
            Console.WriteLine("Trapezoid height is: " + h.ToString());
            double dxR = trpz.GetLeftBaseRadianAngle();
            Console.WriteLine("Trapezoid left base angle is: " + dxR.ToString() + " Radians");
            double dyR = trpz.GetRightBaseRadianAngle();
            Console.WriteLine("Trapezoid right base angle is: " + dyR.ToString() + " Radians");
            double dxD = trpz.GetLeftBaseDegreeAngle();
            Console.WriteLine("Trapezoid left base angle is: " + dxD.ToString() + " Degrees");
            double dyD = trpz.GetRightBaseDegreeAngle();
            Console.WriteLine("Trapezoid right base angle is: " + dyD.ToString() + " Degrees");
        }
    }
}
open System
/// The following class represents simple functionality of the trapezoid.
type MathTrapezoidSample(longbase, shortbase, leftLeg, rightLeg) =
    member _.GetRightSmallBase() =
        (Math.Pow(rightLeg, 2.) - Math.Pow(leftLeg, 2.) + Math.Pow(longbase, 2.) + Math.Pow(shortbase, 2.) - 2. * shortbase * longbase) / (2. * (longbase - shortbase))
    member this.GetHeight() =
        let x = this.GetRightSmallBase()
        Math.Sqrt(Math.Pow(rightLeg, 2.) - Math.Pow(x, 2.))
    member this.GetSquare() =
        this.GetHeight() * longbase / 2.
    member this.GetLeftBaseRadianAngle() =
        let sinX = this.GetHeight() / leftLeg
        Math.Round(Math.Asin sinX,2)
    member this.GetRightBaseRadianAngle() =
        let x = this.GetRightSmallBase()
        let cosX = (Math.Pow(rightLeg, 2.) + Math.Pow(x, 2.) - Math.Pow(this.GetHeight(), 2.))/(2. * x * rightLeg)
        Math.Round(Math.Acos cosX, 2)
    member this.GetLeftBaseDegreeAngle() =
        let x = this.GetLeftBaseRadianAngle() * 180. / Math.PI
        Math.Round(x, 2)
    member this.GetRightBaseDegreeAngle() =
        let x = this.GetRightBaseRadianAngle() * 180. / Math.PI
        Math.Round(x, 2)
let trpz = MathTrapezoidSample(20., 10., 8., 6.)
printfn "The trapezoid's bases are 20.0 and 10.0, the trapezoid's legs are 8.0 and 6.0"
let h = trpz.GetHeight()
printfn $"Trapezoid height is: {h}"
let dxR = trpz.GetLeftBaseRadianAngle()
printfn $"Trapezoid left base angle is: {dxR} Radians"
let dyR = trpz.GetRightBaseRadianAngle()
printfn $"Trapezoid right base angle is: {dyR} Radians"
let dxD = trpz.GetLeftBaseDegreeAngle()
printfn $"Trapezoid left base angle is: {dxD} Degrees"
let dyD = trpz.GetRightBaseDegreeAngle()
printfn $"Trapezoid right base angle is: {dyD} Degrees"
'The following class represents simple functionality of the trapezoid.
Class MathTrapezoidSample
    Private m_longBase As Double
    Private m_shortBase As Double
    Private m_leftLeg As Double
    Private m_rightLeg As Double
    Public Sub New(ByVal longbase As Double, ByVal shortbase As Double, ByVal leftLeg As Double, ByVal rightLeg As Double)
        m_longBase = Math.Abs(longbase)
        m_shortBase = Math.Abs(shortbase)
        m_leftLeg = Math.Abs(leftLeg)
        m_rightLeg = Math.Abs(rightLeg)
    End Sub
    Private Function GetRightSmallBase() As Double
        GetRightSmallBase = (Math.Pow(m_rightLeg, 2) - Math.Pow(m_leftLeg, 2) + Math.Pow(m_longBase, 2) + Math.Pow(m_shortBase, 2) - 2 * m_shortBase * m_longBase) / (2 * (m_longBase - m_shortBase))
    End Function
    Public Function GetHeight() As Double
        Dim x As Double = GetRightSmallBase()
        GetHeight = Math.Sqrt(Math.Pow(m_rightLeg, 2) - Math.Pow(x, 2))
    End Function
    Public Function GetSquare() As Double
        GetSquare = GetHeight() * m_longBase / 2
    End Function
    Public Function GetLeftBaseRadianAngle() As Double
        Dim sinX As Double = GetHeight() / m_leftLeg
        GetLeftBaseRadianAngle = Math.Round(Math.Asin(sinX), 2)
    End Function
    Public Function GetRightBaseRadianAngle() As Double
        Dim x As Double = GetRightSmallBase()
        Dim cosX As Double = (Math.Pow(m_rightLeg, 2) + Math.Pow(x, 2) - Math.Pow(GetHeight(), 2)) / (2 * x * m_rightLeg)
        GetRightBaseRadianAngle = Math.Round(Math.Acos(cosX), 2)
    End Function
    Public Function GetLeftBaseDegreeAngle() As Double
        Dim x As Double = GetLeftBaseRadianAngle() * 180 / Math.PI
        GetLeftBaseDegreeAngle = Math.Round(x, 2)
    End Function
    Public Function GetRightBaseDegreeAngle() As Double
        Dim x As Double = GetRightBaseRadianAngle() * 180 / Math.PI
        GetRightBaseDegreeAngle = Math.Round(x, 2)
    End Function
    Public Shared Sub Main()
        Dim trpz As MathTrapezoidSample = New MathTrapezoidSample(20, 10, 8, 6)
        Console.WriteLine("The trapezoid's bases are 20.0 and 10.0, the trapezoid's legs are 8.0 and 6.0")
        Dim h As Double = trpz.GetHeight()
        Console.WriteLine("Trapezoid height is: " + h.ToString())
        Dim dxR As Double = trpz.GetLeftBaseRadianAngle()
        Console.WriteLine("Trapezoid left base angle is: " + dxR.ToString() + " Radians")
        Dim dyR As Double = trpz.GetRightBaseRadianAngle()
        Console.WriteLine("Trapezoid right base angle is: " + dyR.ToString() + " Radians")
        Dim dxD As Double = trpz.GetLeftBaseDegreeAngle()
        Console.WriteLine("Trapezoid left base angle is: " + dxD.ToString() + " Degrees")
        Dim dyD As Double = trpz.GetRightBaseDegreeAngle()
        Console.WriteLine("Trapezoid right base angle is: " + dyD.ToString() + " Degrees")
    End Sub
End Class
Remarks
The value of this field is 3.1415926535897931.