Math.Exp(Double) Methode
Definition
Wichtig
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Gibt e den Wert zurück, der an die angegebene Potenz angehoben wird.
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
Parameter
- d
- Double
Eine Zahl, die eine Potenz angibt.
Gibt zurück
Die Zahl e , die an die Potenz dangehoben wird. Wenn d dieser NaN Wert gleich oder PositiveInfinitygleich ist, wird dieser Wert zurückgegeben. Wenn d gleich NegativeInfinity, wird 0 zurückgegeben.
Beispiele
Im folgenden Beispiel werden Exp bestimmte exponentielle und logarithmische Identitäten für ausgewählte Werte ausgewertet.
// 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
Hinweise
e ist eine mathematische Konstante, deren Wert ungefähr 2,71828 beträgt.
Verwenden Sie die Pow Methode, um Die Befugnisse anderer Basisen zu berechnen.
Exp ist die Umkehrung von Log.
Diese Methode ruft die zugrunde liegende C-Laufzeit auf, und das genaue Ergebnis oder der gültige Eingabebereich kann sich zwischen verschiedenen Betriebssystemen oder Architekturen unterscheiden.