log2 : log2 « math.h « C Tutorial






ItemValue
Header filemath.h
Declarationfloat log2f(float num);
double log2(double num);
long double log2l(long double num);
Returnreturns the base 2 logarithm for num.


#include <math.h>
  #include <stdio.h>

  int main(void)
  {
    double val = 1.0;

    do {
      printf("%f %f\n", val, log2(val));
      val++;
    } while (val<11.0);

    return 0;
  }
1.000000 0.000000
2.000000 1.000000
3.000000 1.584963
4.000000 2.000000
5.000000 2.321928
6.000000 2.584963
7.000000 2.807355
8.000000 3.000000
9.000000 3.169925
10.000000 3.321928








19.45.log2
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