1 #include <u.h> 2 #include <libc.h> 3 /* 4 * floor and ceil-- greatest integer <= arg 5 * (resp least >=) 6 */ 7 8 double 9 floor(double d) 10 { 11 double fract; 12 13 if(d < 0) { 14 fract = modf(-d, &d); 15 if(fract != 0.0) 16 d += 1; 17 d = -d; 18 } else 19 modf(d, &d); 20 return d; 21 } 22 23 double 24 ceil(double d) 25 { 26 return -floor(-d); 27 } 28