C++ Math lgamma()

The lgamma() function computes the logarithm of a gamma function of an argument passed to the function.

Suppose a number is x:

Syntax

Parameter

x: It is a floating point value.

Return value

It returns the logarithm of a gamma function of value x.

Example 1

Let's see the simple example when the value of x is 2.

Output:

Value of x is : 2
lgamma(x) :0

In the above example, the value of x is 2. Therefore, the function lgamma() returns 0 value.

Example 2

Let's see the simple example when the value of x is 0.

Output:

Value of x is : 0
lgamma(x) : inf

In the above example, the value of x is zero. Therefore, the function lgamma() returns +∞.

Example 3

Let's see the simple example when the value of x is a negative integer.

Output:

Value of x is : -5
lgamma(x) : inf

In the above example, the value of x is a negative integer. Therefore, the function lgamma() returns +∞.

Example 4

Let's see the simple example when the value of x is nan.

Output:

Value of x is : -nan
lgamma(x) :-nan

In the above example, the value of x is nan. Therefore, the function lgamma() returns nan.