Math.Exp(Double) メソッド

リファレンス

定義

名前空間:: System

アセンブリ:: System.Runtime.Extensions.dll

アセンブリ:: System.Runtime.dll

アセンブリ:: mscorlib.dll

アセンブリ:: netstandard.dll

ソース:: Math.cs

ソース:: Math.cs

ソース:: Math.cs

重要

一部の情報は、リリース前に大きく変更される可能性があるプレリリースされた製品に関するものです。 Microsoft は、ここに記載されている情報について、明示または黙示を問わず、一切保証しません。

指定した値で e を累乗した値を返します。

public:
 static double Exp(double d);

public static double Exp (double d);

static member Exp : double -> double

Public Shared Function Exp (d As Double) As Double

パラメーター

d: Double

累乗を指定する数値。

戻り値

Double

数値 e を d で累乗した値。 d が NaN または PositiveInfinity のいずれかに等しい場合は、その値が返されます。 d が NegativeInfinity に等しい場合は、0 が返されます。

例

次の例では、を使用 Exp して、選択した値の特定の指数 ID と対数 ID を評価します。

// Example for the Math::Exp( double ) method.
using namespace System;

// Evaluate logarithmic/exponential identity with a given argument.
void UseLnExp( double arg )
{
   
   // Evaluate e ^ ln(X) == ln(e ^ X) == X.
   Console::WriteLine( "\n      Math::Exp(Math::Log({0})) == {1:E16}\n"
   "      Math::Log(Math::Exp({0})) == {2:E16}", arg, Math::Exp( Math::Log( arg ) ), Math::Log( Math::Exp( arg ) ) );
}


// Evaluate exponential identities that are functions of two arguments.
void UseTwoArgs( double argX, double argY )
{
   
   // Evaluate (e ^ X) * (e ^ Y) == e ^ (X + Y).
   Console::WriteLine( "\nMath::Exp({0}) * Math::Exp({1}) == {2:E16}"
   "\n           Math::Exp({0} + {1}) == {3:E16}", argX, argY, Math::Exp( argX ) * Math::Exp( argY ), Math::Exp( argX + argY ) );
   
   // Evaluate (e ^ X) ^ Y == e ^ (X * Y).
   Console::WriteLine( " Math::Pow(Math::Exp({0}), {1}) == {2:E16}"
   "\n           Math::Exp({0} * {1}) == {3:E16}", argX, argY, Math::Pow( Math::Exp( argX ), argY ), Math::Exp( argX * argY ) );
   
   // Evaluate X ^ Y == e ^ (Y * ln(X)).
   Console::WriteLine( "            Math::Pow({0}, {1}) == {2:E16}"
   "\nMath::Exp({1} * Math::Log({0})) == {3:E16}", argX, argY, Math::Pow( argX, argY ), Math::Exp( argY * Math::Log( argX ) ) );
}

int main()
{
   Console::WriteLine( "This example of Math::Exp( double ) "
   "generates the following output.\n" );
   Console::WriteLine( "Evaluate [e ^ ln(X) == ln(e ^ X) == X] "
   "with selected values for X:" );
   UseLnExp( 0.1 );
   UseLnExp( 1.2 );
   UseLnExp( 4.9 );
   UseLnExp( 9.9 );
   Console::WriteLine( "\nEvaluate these identities with "
   "selected values for X and Y:" );
   Console::WriteLine( "   (e ^ X) * (e ^ Y) == e ^ (X + Y)" );
   Console::WriteLine( "   (e ^ X) ^ Y == e ^ (X * Y)" );
   Console::WriteLine( "   X ^ Y == e ^ (Y * ln(X))" );
   UseTwoArgs( 0.1, 1.2 );
   UseTwoArgs( 1.2, 4.9 );
   UseTwoArgs( 4.9, 9.9 );
}

/*
This example of Math::Exp( double ) generates the following output.

Evaluate [e ^ ln(X) == ln(e ^ X) == X] with selected values for X:

      Math::Exp(Math::Log(0.1)) == 1.0000000000000001E-001
      Math::Log(Math::Exp(0.1)) == 1.0000000000000008E-001

      Math::Exp(Math::Log(1.2)) == 1.2000000000000000E+000
      Math::Log(Math::Exp(1.2)) == 1.2000000000000000E+000

      Math::Exp(Math::Log(4.9)) == 4.9000000000000012E+000
      Math::Log(Math::Exp(4.9)) == 4.9000000000000004E+000

      Math::Exp(Math::Log(9.9)) == 9.9000000000000004E+000
      Math::Log(Math::Exp(9.9)) == 9.9000000000000004E+000

Evaluate these identities with selected values for X and Y:
   (e ^ X) * (e ^ Y) == e ^ (X + Y)
   (e ^ X) ^ Y == e ^ (X * Y)
   X ^ Y == e ^ (Y * ln(X))

Math::Exp(0.1) * Math::Exp(1.2) == 3.6692966676192444E+000
           Math::Exp(0.1 + 1.2) == 3.6692966676192444E+000
 Math::Pow(Math::Exp(0.1), 1.2) == 1.1274968515793757E+000
           Math::Exp(0.1 * 1.2) == 1.1274968515793757E+000
            Math::Pow(0.1, 1.2) == 6.3095734448019331E-002
Math::Exp(1.2 * Math::Log(0.1)) == 6.3095734448019344E-002

Math::Exp(1.2) * Math::Exp(4.9) == 4.4585777008251705E+002
           Math::Exp(1.2 + 4.9) == 4.4585777008251716E+002
 Math::Pow(Math::Exp(1.2), 4.9) == 3.5780924170885260E+002
           Math::Exp(1.2 * 4.9) == 3.5780924170885277E+002
            Math::Pow(1.2, 4.9) == 2.4433636334442981E+000
Math::Exp(4.9 * Math::Log(1.2)) == 2.4433636334442981E+000

Math::Exp(4.9) * Math::Exp(9.9) == 2.6764450551890982E+006
           Math::Exp(4.9 + 9.9) == 2.6764450551891015E+006
 Math::Pow(Math::Exp(4.9), 9.9) == 1.1684908531676833E+021
           Math::Exp(4.9 * 9.9) == 1.1684908531676829E+021
            Math::Pow(4.9, 9.9) == 6.8067718210957060E+006
Math::Exp(9.9 * Math::Log(4.9)) == 6.8067718210956985E+006
*/

// Example for the Math.Exp( double ) method.
using System;

class ExpDemo
{
    public static void Main()
    {
        Console.WriteLine(
            "This example of Math.Exp( double ) " +
            "generates the following output.\n" );
        Console.WriteLine(
            "Evaluate [e ^ ln(X) == ln(e ^ X) == X] " +
            "with selected values for X:" );

        UseLnExp(0.1);
        UseLnExp(1.2);
        UseLnExp(4.9);
        UseLnExp(9.9);

        Console.WriteLine(
            "\nEvaluate these identities with " +
            "selected values for X and Y:" );
        Console.WriteLine( "   (e ^ X) * (e ^ Y) == e ^ (X + Y)" );
        Console.WriteLine( "   (e ^ X) ^ Y == e ^ (X * Y)" );
        Console.WriteLine( "   X ^ Y == e ^ (Y * ln(X))" );

        UseTwoArgs(0.1, 1.2);
        UseTwoArgs(1.2, 4.9);
        UseTwoArgs(4.9, 9.9);
    }

    // Evaluate logarithmic/exponential identity with a given argument.
    static void UseLnExp(double arg)
    {
        // Evaluate e ^ ln(X) == ln(e ^ X) == X.
        Console.WriteLine(
            "\n      Math.Exp(Math.Log({0})) == {1:E16}\n" +
            "      Math.Log(Math.Exp({0})) == {2:E16}",
            arg, Math.Exp(Math.Log(arg)), Math.Log(Math.Exp(arg)) );
    }

    // Evaluate exponential identities that are functions of two arguments.
    static void UseTwoArgs(double argX, double argY)
    {
        // Evaluate (e ^ X) * (e ^ Y) == e ^ (X + Y).
        Console.WriteLine(
            "\nMath.Exp({0}) * Math.Exp({1}) == {2:E16}" +
            "\n          Math.Exp({0} + {1}) == {3:E16}",
            argX, argY, Math.Exp(argX) * Math.Exp(argY),
            Math.Exp(argX + argY) );

        // Evaluate (e ^ X) ^ Y == e ^ (X * Y).
        Console.WriteLine(
            " Math.Pow(Math.Exp({0}), {1}) == {2:E16}" +
            "\n          Math.Exp({0} * {1}) == {3:E16}",
            argX, argY, Math.Pow(Math.Exp(argX), argY),
            Math.Exp(argX * argY) );

        // Evaluate X ^ Y == e ^ (Y * ln(X)).
        Console.WriteLine(
            "           Math.Pow({0}, {1}) == {2:E16}" +
            "\nMath.Exp({1} * Math.Log({0})) == {3:E16}",
            argX, argY, Math.Pow(argX, argY),
            Math.Exp(argY * Math.Log(argX)) );
    }
}

/*
This example of Math.Exp( double ) generates the following output.

Evaluate [e ^ ln(X) == ln(e ^ X) == X] with selected values for X:

      Math.Exp(Math.Log(0.1)) == 1.0000000000000001E-001
      Math.Log(Math.Exp(0.1)) == 1.0000000000000008E-001

      Math.Exp(Math.Log(1.2)) == 1.2000000000000000E+000
      Math.Log(Math.Exp(1.2)) == 1.2000000000000000E+000

      Math.Exp(Math.Log(4.9)) == 4.9000000000000012E+000
      Math.Log(Math.Exp(4.9)) == 4.9000000000000004E+000

      Math.Exp(Math.Log(9.9)) == 9.9000000000000004E+000
      Math.Log(Math.Exp(9.9)) == 9.9000000000000004E+000

Evaluate these identities with selected values for X and Y:
   (e ^ X) * (e ^ Y) == e ^ (X + Y)
   (e ^ X) ^ Y == e ^ (X * Y)
   X ^ Y == e ^ (Y * ln(X))

Math.Exp(0.1) * Math.Exp(1.2) == 3.6692966676192444E+000
          Math.Exp(0.1 + 1.2) == 3.6692966676192444E+000
 Math.Pow(Math.Exp(0.1), 1.2) == 1.1274968515793757E+000
          Math.Exp(0.1 * 1.2) == 1.1274968515793757E+000
           Math.Pow(0.1, 1.2) == 6.3095734448019331E-002
Math.Exp(1.2 * Math.Log(0.1)) == 6.3095734448019344E-002

Math.Exp(1.2) * Math.Exp(4.9) == 4.4585777008251705E+002
          Math.Exp(1.2 + 4.9) == 4.4585777008251716E+002
 Math.Pow(Math.Exp(1.2), 4.9) == 3.5780924170885260E+002
          Math.Exp(1.2 * 4.9) == 3.5780924170885277E+002
           Math.Pow(1.2, 4.9) == 2.4433636334442981E+000
Math.Exp(4.9 * Math.Log(1.2)) == 2.4433636334442981E+000

Math.Exp(4.9) * Math.Exp(9.9) == 2.6764450551890982E+006
          Math.Exp(4.9 + 9.9) == 2.6764450551891015E+006
 Math.Pow(Math.Exp(4.9), 9.9) == 1.1684908531676833E+021
          Math.Exp(4.9 * 9.9) == 1.1684908531676829E+021
           Math.Pow(4.9, 9.9) == 6.8067718210957060E+006
Math.Exp(9.9 * Math.Log(4.9)) == 6.8067718210956985E+006
*/

// Example for the Math.Exp( double ) method.
// The exp function may be used instead.

open System
printfn "This example of Math.Exp( double ) generates the following output.\n"
printfn "Evaluate [e ^ ln(X) = ln(e ^ X) = X] with selected values for X:"

// Evaluate logarithmic/exponential identity with a given argument.
let useLnExp arg =
    // Evaluate e ^ ln(X) = ln(e ^ X) = X.
    printfn $"\n      Math.Exp(Math.Log({arg})) = {Math.Exp(Math.Log arg):E16}\n      Math.Log(Math.Exp({arg})) = {Math.Log(Math.Exp arg):E16}"

// Evaluate exponential identities that are functions of two arguments.
let useTwoArgs argX argY =
    // Evaluate (e ^ X) * (e ^ Y) = e ^ (X + Y).
    printfn $"""
Math.Exp({argX}) * Math.Exp({argY}) = {Math.Exp argX * Math.Exp argY:E16}" +
          Math.Exp({argX} + {argY}) = {Math.Exp(argX + argY):E16}"""

    // Evaluate (e ^ X) ^ Y = e ^ (X * Y).
    printfn $" Math.Pow(Math.Exp({argX}), {argY}) = {Math.Pow(Math.Exp argX, argY):E16}\n          Math.Exp({argX} * {argY}) = {Math.Exp(argX * argY):E16}"

    // Evaluate X ^ Y = e ^ (Y * ln(X)).
    printfn $"           Math.Pow({argX}, {argY}) = {Math.Pow(argX, argY):E16}\nMath.Exp({argY} * Math.Log({argX})) = {Math.Exp(argY * Math.Log argX):E16}"

useLnExp 0.1
useLnExp 1.2
useLnExp 4.9
useLnExp 9.9

printfn "\nEvaluate these identities with selected values for X and Y:"
printfn "   (e ^ X) * (e ^ Y) = e ^ (X + Y)"
printfn "   (e ^ X) ^ Y = e ^ (X * Y)"
printfn "   X ^ Y = e ^ (Y * ln(X))"

useTwoArgs 0.1 1.2
useTwoArgs 1.2 4.9
useTwoArgs 4.9 9.9

// This example of Math.Exp( double ) generates the following output.
//
// Evaluate [e ^ ln(X) = ln(e ^ X) = X] with selected values for X:
//
//       Math.Exp(Math.Log(0.1)) = 1.0000000000000001E-001
//       Math.Log(Math.Exp(0.1)) = 1.0000000000000008E-001
//
//       Math.Exp(Math.Log(1.2)) = 1.2000000000000000E+000
//       Math.Log(Math.Exp(1.2)) = 1.2000000000000000E+000
//
//       Math.Exp(Math.Log(4.9)) = 4.9000000000000012E+000
//       Math.Log(Math.Exp(4.9)) = 4.9000000000000004E+000
//
//       Math.Exp(Math.Log(9.9)) = 9.9000000000000004E+000
//       Math.Log(Math.Exp(9.9)) = 9.9000000000000004E+000
//
// Evaluate these identities with selected values for X and Y:
//    (e ^ X) * (e ^ Y) = e ^ (X + Y)
//    (e ^ X) ^ Y = e ^ (X * Y)
//    X ^ Y = e ^ (Y * ln(X))
//
// Math.Exp(0.1) * Math.Exp(1.2) = 3.6692966676192444E+000
//           Math.Exp(0.1 + 1.2) = 3.6692966676192444E+000
//  Math.Pow(Math.Exp(0.1), 1.2) = 1.1274968515793757E+000
//           Math.Exp(0.1 * 1.2) = 1.1274968515793757E+000
//            Math.Pow(0.1, 1.2) = 6.3095734448019331E-002
// Math.Exp(1.2 * Math.Log(0.1)) = 6.3095734448019344E-002
//
// Math.Exp(1.2) * Math.Exp(4.9) = 4.4585777008251705E+002
//           Math.Exp(1.2 + 4.9) = 4.4585777008251716E+002
//  Math.Pow(Math.Exp(1.2), 4.9) = 3.5780924170885260E+002
//           Math.Exp(1.2 * 4.9) = 3.5780924170885277E+002
//            Math.Pow(1.2, 4.9) = 2.4433636334442981E+000
// Math.Exp(4.9 * Math.Log(1.2)) = 2.4433636334442981E+000
//
// Math.Exp(4.9) * Math.Exp(9.9) = 2.6764450551890982E+006
//           Math.Exp(4.9 + 9.9) = 2.6764450551891015E+006
//  Math.Pow(Math.Exp(4.9), 9.9) = 1.1684908531676833E+021
//           Math.Exp(4.9 * 9.9) = 1.1684908531676829E+021
//            Math.Pow(4.9, 9.9) = 6.8067718210957060E+006
// Math.Exp(9.9 * Math.Log(4.9)) = 6.8067718210956985E+006

' Example for the Math.Exp( Double ) method.
Module ExpDemo
   
    Sub Main()
        Console.WriteLine( _
            "This example of Math.Exp( Double ) " & _
            "generates the following output." & vbCrLf)
        Console.WriteLine( _
            "Evaluate [e ^ ln(X) == ln(e ^ X) == X] " & _
            "with selected values for X:")

        UseLnExp(0.1)
        UseLnExp(1.2)
        UseLnExp(4.9)
        UseLnExp(9.9)
          
        Console.WriteLine( vbCrLf & _
            "Evaluate these identities with selected values for X and Y:")
        Console.WriteLine("   (e ^ X) * (e ^ Y) = e ^ (X + Y)")
        Console.WriteLine("   (e ^ X) ^ Y = e ^ (X * Y)")
        Console.WriteLine("   X ^ Y = e ^ (Y * ln(X))")
          
        UseTwoArgs(0.1, 1.2)
        UseTwoArgs(1.2, 4.9)
        UseTwoArgs(4.9, 9.9)
    End Sub
       
    ' Evaluate logarithmic/exponential identity with a given argument.
    Sub UseLnExp(arg As Double)

        ' Evaluate e ^ ln(X) = ln(e ^ X) = X.
        Console.WriteLine( _
            vbCrLf & "      Math.Exp(Math.Log({0})) = {1:E16}" + _
            vbCrLf & "      Math.Log(Math.Exp({0})) = {2:E16}", _
            arg, Math.Exp(Math.Log(arg)), Math.Log(Math.Exp(arg)))
    End Sub
       
    ' Evaluate exponential identities that are functions of two arguments.
    Sub UseTwoArgs(argX As Double, argY As Double)

        ' Evaluate (e ^ X) * (e ^ Y) = e ^ (X + Y).
        Console.WriteLine( _
            vbCrLf & "Math.Exp({0}) * Math.Exp({1}) = {2:E16}" + _
            vbCrLf & "          Math.Exp({0} + {1}) = {3:E16}", _
            argX, argY, Math.Exp(argX) * Math.Exp(argY), _
            Math.Exp((argX + argY)))
          
        ' Evaluate (e ^ X) ^ Y = e ^ (X * Y).
        Console.WriteLine( _
            " Math.Pow(Math.Exp({0}), {1}) = {2:E16}" + _
            vbCrLf & "          Math.Exp({0} * {1}) = {3:E16}", _
            argX, argY, Math.Pow(Math.Exp(argX), argY), _
            Math.Exp((argX * argY)))
          
        ' Evaluate X ^ Y = e ^ (Y * ln(X)).
        Console.WriteLine( _
            "           Math.Pow({0}, {1}) = {2:E16}" + _
            vbCrLf & "Math.Exp({1} * Math.Log({0})) = {3:E16}", _
            argX, argY, Math.Pow(argX, argY), _
            Math.Exp((argY * Math.Log(argX))))

    End Sub
End Module 'ExpDemo

' This example of Math.Exp( Double ) generates the following output.
' 
' Evaluate [e ^ ln(X) == ln(e ^ X) == X] with selected values for X:
' 
'       Math.Exp(Math.Log(0.1)) = 1.0000000000000001E-001
'       Math.Log(Math.Exp(0.1)) = 1.0000000000000008E-001
' 
'       Math.Exp(Math.Log(1.2)) = 1.2000000000000000E+000
'       Math.Log(Math.Exp(1.2)) = 1.2000000000000000E+000
' 
'       Math.Exp(Math.Log(4.9)) = 4.9000000000000012E+000
'       Math.Log(Math.Exp(4.9)) = 4.9000000000000004E+000
' 
'       Math.Exp(Math.Log(9.9)) = 9.9000000000000004E+000
'       Math.Log(Math.Exp(9.9)) = 9.9000000000000004E+000
' 
' Evaluate these identities with selected values for X and Y:
'    (e ^ X) * (e ^ Y) = e ^ (X + Y)
'    (e ^ X) ^ Y = e ^ (X * Y)
'    X ^ Y = e ^ (Y * ln(X))
' 
' Math.Exp(0.1) * Math.Exp(1.2) = 3.6692966676192444E+000
'           Math.Exp(0.1 + 1.2) = 3.6692966676192444E+000
'  Math.Pow(Math.Exp(0.1), 1.2) = 1.1274968515793757E+000
'           Math.Exp(0.1 * 1.2) = 1.1274968515793757E+000
'            Math.Pow(0.1, 1.2) = 6.3095734448019331E-002
' Math.Exp(1.2 * Math.Log(0.1)) = 6.3095734448019344E-002
' 
' Math.Exp(1.2) * Math.Exp(4.9) = 4.4585777008251705E+002
'           Math.Exp(1.2 + 4.9) = 4.4585777008251716E+002
'  Math.Pow(Math.Exp(1.2), 4.9) = 3.5780924170885260E+002
'           Math.Exp(1.2 * 4.9) = 3.5780924170885277E+002
'            Math.Pow(1.2, 4.9) = 2.4433636334442981E+000
' Math.Exp(4.9 * Math.Log(1.2)) = 2.4433636334442981E+000
' 
' Math.Exp(4.9) * Math.Exp(9.9) = 2.6764450551890982E+006
'           Math.Exp(4.9 + 9.9) = 2.6764450551891015E+006
'  Math.Pow(Math.Exp(4.9), 9.9) = 1.1684908531676833E+021
'           Math.Exp(4.9 * 9.9) = 1.1684908531676829E+021
'            Math.Pow(4.9, 9.9) = 6.8067718210957060E+006
' Math.Exp(9.9 * Math.Log(4.9)) = 6.8067718210956985E+006

注釈

e は、値が約 2.71828 である数学定数です。

メソッドを Pow 使用して、他の基底の累乗を計算します。

Exp はの逆関数 Logです。

このメソッドは基になる C ランタイムを呼び出します。正確な結果または有効な入力範囲は、オペレーティングシステムやアーキテクチャによって異なる場合があります。

適用対象

次の方法で共有

Math.Exp(Double) メソッド

定義

パラメーター

戻り値

例

注釈

適用対象

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