Math.Log10(Double) Method

Definition

Namespace:

System

Assemblies:

netstandard.dll, System.Runtime.dll

Source:

Math.cs

Returns the base 10 logarithm of a specified number.

C#

public static double Log10(double d);

Parameters

d

Double

A number whose logarithm is to be found.

Returns

Double

One of the values in the following table.

d parameter	Return value
Positive	The base 10 log of d; that is, log 10d.
Zero	NegativeInfinity
Negative	NaN
Equal to NaN	NaN
Equal to PositiveInfinity	PositiveInfinity

Examples

The following example uses the Log10 method to return the base 10 logarithm for selected values.

C#

using System;

public class Example
{
   public static void Main()
   {
      double[] numbers = {-1, 0, .105, .5, .798, 1, 4, 6.9, 10, 50,
                          100, 500, 1000, Double.MaxValue};

      foreach (double number in numbers)
         Console.WriteLine("The base 10 log of {0} is {1}.",
                           number, Math.Log10(number));
   }
}
// The example dislays the following output:
//       The base 10 log of -1 is NaN.
//       The base 10 log of 0 is -Infinity.
//       The base 10 log of 0.105 is -0.978810700930062.
//       The base 10 log of 0.5 is -0.301029995663981.
//       The base 10 log of 0.798 is -0.0979971086492706.
//       The base 10 log of 1 is 0.
//       The base 10 log of 4 is 0.602059991327962.
//       The base 10 log of 6.9 is 0.838849090737255.
//       The base 10 log of 10 is 1.
//       The base 10 log of 50 is 1.69897000433602.
//       The base 10 log of 100 is 2.
//       The base 10 log of 500 is 2.69897000433602.
//       The base 10 log of 1000 is 3.
//       The base 10 log of 1.79769313486232E+308 is 308.254715559917.

Remarks

Parameter d is specified as a base 10 number.

This method calls into the underlying C runtime, and the exact result or valid input range may differ between different operating systems or architectures.

Applies to