log10


function
<cmath>
     double log10 (      double x );
      float log10 (       float x );
long double log10 ( long double x );

Compute common logarithm

Returns the common (base-10) logarithm of x.

In C++, this function is overloaded in <complex> and <valarray> (see complex log10 and valarray log10).

Parameters

x
Floating point value.
If the argument is negative, a domain error occurs, setting the global variable errno to the value EDOM.
If it is zero, the function returns a negative HUGE_VAL and sets the value of the global variable errno to the ERANGE value.


Return Value

Common logarithm of x, for values of x greater than zero.

Portability

In C, only the double version of this function exists with this name.

Example

1
2
3
4
5
6
7
8
9
10
11
12
/* log10 example */
#include <stdio.h>
#include <math.h>

int main ()
{
  double param, result;
  param = 1000.0;
  result = log10 (param);
  printf ("log10(%lf) = %lf\n", param, result );
  return 0;
}


Output:

log10(1000.000000) = 3.000000


See also