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.
Parameter | Return value |
---|---|
x= 1 or x=2 | 0 |
x= ±0 | +∞ |
x= -ve integer or ±∞ | +∞ |
x= nan | nan |
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.