C log() function

C log() function - Calculate natural logarithm

Syntax:

double log(double x)

The log() function is used to calculate the natural logarithm (base e) of x.

Parameters:

Return value from log()

• Upon successful completion, the function returns the natural logarithm of x.

Example: log() function

The following example shows the usage of log() function.

#include <math.h>
#include <stdio.h> 
int main(void)
{
    double x = 1.0, y;
    y = log(x);
    printf("The natural logarithm of %lf is %lf\n", x, y);
	x = 10.0;
    y = log(x);
    printf("The natural logarithm of %lf is %lf\n", x, y);
   	x = 1000.0;
    y = log(x);
    printf("The natural logarithm of %lf is %lf\n", x, y);
}

Output:

The natural logarithm of 1.000000 is 0.000000
The natural logarithm of 10.000000 is 2.302585
The natural logarithm of 1000.000000 is 6.907755

C Programming Code Editor:

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