# Complex.Log Method (Complex)

.NET Framework (current version)

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Returns the natural (base e) logarithm of a specified complex number.

Namespace:   System.Numerics
Assembly:  System.Numerics (in System.Numerics.dll)

## Syntax

```public static Complex Log(
Complex value
)
```

#### Parameters

value
Type: System.Numerics.Complex

A complex number.

#### Return Value

Type: System.Numerics.Complex

The natural (base e) logarithm of value.

## Remarks

The Log(Complex) method for complex numbers corresponds to the Math.Log(Double) method for real numbers.

## Examples

The following example illustrates the Log method. It shows that, with some allowance for the lack of precision of the Double data type, passing the value returned by the Log method to the Exp method returns the original Complex value.

```using System;
using System.Numerics;

public class Example
{
public static void Main()
{
Complex[] values = { new Complex(1.53, 9.26),
new Complex(2.53, -8.12),
new Complex(-2.81, 5.32),
new Complex(-1.09, -3.43),
new Complex(Double.MinValue/2, Double.MinValue/2) };
foreach (Complex value in values)
Console.WriteLine("Exp(Log({0}) = {1}", value,
Complex.Exp(Complex.Log(value)));
}
}
// The example displays the following output:
//       Exp(Log((1.53, 9.26)) = (1.53, 9.26)
//       Exp(Log((2.53, -8.12)) = (2.53, -8.12)
//       Exp(Log((-2.81, 5.32)) = (-2.81, 5.32)
//       Exp(Log((-1.09, -3.43)) = (-1.09, -3.43)
//       Exp(Log((-8.98846567431158E+307, -8.98846567431158E+307)) = (-8.98846567431161E+307, -8.98846567431161E+307)
```

## Version Information

Universal Windows Platform
Available since 8
.NET Framework
Available since 4.0
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 4.0
Windows Phone
Available since 8.1