mixed_entropy.cc

#include <cstdio>
#include <cmath>

double mixed_entropy(double e, double n) {
  if (n == 0.0) {
    return 0.0;
  }
  return log(n) - e / n;
}

int main(int argc, char** argv) {
  double n = 3;
  double e_d = 3 * log(3);
  double e_e = - e_d / 3 + log(3);

  double d = 0.0;

  d = e_e;
  fprintf(stdout, "d = %g\n", d);

  d = (n == 0.0) ? 0.0 : (log(n) - e_d / n);
  fprintf(stdout, "d = %g\n", d);

  d = mixed_entropy(e_d, n);
  fprintf(stdout, "d = %g\n", d);

  return 0;
}