作者:VB.NET开发
项目:Syste
Module Example
Sub Main()
Console.WriteLine( _
" Evaluate this identity with selected values for X:")
Console.WriteLine(" ln(x) = 1 / log[X](B)")
Console.WriteLine()
Dim XArgs() As Double = { 1.2, 4.9, 9.9, 0.1 }
For Each argX As Double In XArgs
' Find natural log of argX.
Console.WriteLine(" Math.Log({0}) = {1:E16}", _
argX, Math.Log(argX))
' Evaluate 1 / log[X](e).
Console.WriteLine(" 1.0 / Math.Log(e, {0}) = {1:E16}", _
argX, 1.0 / Math.Log(Math.E, argX))
Console.WriteLine()
Next
End Sub
End Module
作者:VB.NET开发
项目:Syste
' Example for the Math.Log( Double ) and Math.Log( Double, Double ) methods.
Module LogDLogDD
Sub Main()
Console.WriteLine( _
"This example of Math.Log( Double ) and " + _
"Math.Log( Double, Double )" & vbCrLf & _
"generates the following output." & vbCrLf)
Console.WriteLine( _
"Evaluate these identities with selected " & _
"values for X and B (base):")
Console.WriteLine(" log(B)[X] = 1 / log(X)[B]")
Console.WriteLine(" log(B)[X] = ln[X] / ln[B]")
Console.WriteLine(" log(B)[X] = log(B)[e] * ln[X]")
UseBaseAndArg(0.1, 1.2)
UseBaseAndArg(1.2, 4.9)
UseBaseAndArg(4.9, 9.9)
UseBaseAndArg(9.9, 0.1)
End Sub
' Evaluate logarithmic identities that are functions of two arguments.
Sub UseBaseAndArg(argB As Double, argX As Double)
' Evaluate log(B)[X] = 1 / log(X)[B].
Console.WriteLine( _
vbCrLf & " Math.Log({1}, {0}) = {2:E16}" + _
vbCrLf & " 1.0 / Math.Log({0}, {1}) = {3:E16}", _
argB, argX, Math.Log(argX, argB), _
1.0 / Math.Log(argB, argX))
' Evaluate log(B)[X] = ln[X] / ln[B].
Console.WriteLine( _
" Math.Log({1}) / Math.Log({0}) = {2:E16}", _
argB, argX, Math.Log(argX) / Math.Log(argB))
' Evaluate log(B)[X] = log(B)[e] * ln[X].
Console.WriteLine( _
"Math.Log(Math.E, {0}) * Math.Log({1}) = {2:E16}", _
argB, argX, Math.Log(Math.E, argB) * Math.Log(argX))
End Sub
End Module 'LogDLogDD
' This example of Math.Log( Double ) and Math.Log( Double, Double )