/*
 *   mathfncs.c   - Uses math.h functions
 *       fabs  - return absolute value of xx
 *       floor - returns largest integer not greater than xx
 *       pow   - return xx to the yy power
 *       sqrt  - returns square root of xx
 *       ceil  - returns lowest integer not smaller than xx
 *       fmod  - returns floating point remainder of xx/yy
 */
#include <stdio.h>
#include <math.h>  // This line is ESSENCIAL

int main(void)
{
  double xx=2.7;
  double yy=-6.3;
  double aa=10.0;
  double bb=2.0;
  double nn=16.0;
  double ce=9.1;
  double fma=3.5;
  double fmb=3.4;

  printf("The absolute value of %.2f is %.2f\n", xx, fabs(xx) );
  printf("The absolute value of %.2f is %.2f\n", yy, fabs(yy) );
  printf("The absolute value of %.2f is %.2f\n", -xx, fabs(-xx) );

  printf("The largest float-integer number not greater");
  printf("than %.2f is %.2f\n", xx, floor(xx) );

  
  printf("The largest float-integer number not greater");
  printf("than %.2f is %.2f\n", -xx, floor(-xx) );

  printf("The %.2f to the power of %.2f is %.2f\n", aa, bb, pow(aa,bb) );
  printf("The %.2f to the power of %.2f is %.2f\n", aa, -bb, pow(aa,-bb) );

  printf("The square root of %.2f is %.2f\n", nn, sqrt(nn) );

  printf("ceil(x) returns the smallest integer not less than xx:\n");
  printf("ceil of 9.1 is: %.2f\n\n", ceil(ce) );
 
  printf("fmod(x,y) returns floating point remainder, same sign as xx:\n");
  printf("fmod of (3.5, 3.4) is: %.2f\n\n", fmod(fma, fmb) );

  return 0;
}