BigInteger.Log Method (BigInteger, Double)

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Returns the logarithm of a specified number in a specified base.

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

Syntax

'Declaration
Public Shared Function Log ( _
    value As BigInteger, _
    baseValue As Double _
) As Double
public static double Log(
    BigInteger value,
    double baseValue
)

Parameters

Return Value

Type: System.Double
The base baseValue logarithm of value, as shown in the table in the Remarks section.

Exceptions

Exception Condition
ArgumentOutOfRangeException

The log of value is out of range of the Double data type.

Remarks

The value and baseValue parameters are specified as base 10 numbers.

The precise return value of the method depends on the sign of value and on the sign and value of baseValue, as the following table shows.

value parameter

baseValue parameter

Return value

value > 0

(0 < baseValue < 1) -or-(baseValue > 1)

logbaseValue(value)

value < 0

(any value)

Double.NaN

(any value)

baseValue < 0

Double.NaN

value != 1

baseValue = 0

Double.NaN

value != 1

baseValue = Double.PositiveInfinity

Double.NaN

(any value)

baseValue = Double.NaN

Double.NaN

(any value)

baseValue = 1

Double.NaN

value = 0

0 < baseValue < 1

Double.PositiveInfinity

value = 0

baseValue > 1

Double.PositiveInfinity

value = 1

baseValue = 0

0

value = 1

baseValue = Double.PositiveInfinity

0

To calculate the base 10 logarithm of a BigInteger value, call the Log10 method. To calculate the natural logarithm of a number, call the Log(BigInteger) method.

This method corresponds to the Math.Log method for the primitive numeric types.

Version Information

Silverlight

Supported in: 5, 4

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.