Syntax

#include <math.h>
double log(double x);

log calculates the natural logarithm (base e) of x.

log returns the computed value. If x is negative, log sets errno to EDOM and may return the value -HUGE_VAL. If x is zero, log returns the value -HUGE_VAL, and may set errno to ERANGE.

This example calculates the natural logarithm of 1000.0.

#include <math.h>

int main(void)
{
   double x = 1000.0,y;

   y = log(x);
   printf("The natural logarithm of %lf is %lf\n", x, y);
   return 0;

   /****************************************************************************
      The output should be:

      The natural logarithm of 1000.000000 is 6.907755
   ****************************************************************************/
}

• exp
  
• log10
  
• pow

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