C log() Prototype
double log( double arg );
The log() function takes a single argument and returns a value of type float.
[Mathematics] logex = log(x) [In C programming]
It is defined in <math.h> header file.
In order to find the log() of long double or float numbers, you can use the following prototype.
long double logl( long double arg); float logf(float arg);
C log() Arguments
| Argument | remarks |
|---|---|
| arg > 0 (Greater than zero) | Finds the natural log of the argument |
| arg < 0 (Less than zero) | Shows run-time error |
Example: C log() function
#include <stdio.h>
#include <math.h>
int main()
{
double num = 5.6, result;
result = log(num);
printf("log(%.1f) = %.2f", num, result);
return 0;
}
Output
log(5.6) = 1.72