test/math/gamma.c

   1 #include <math.h>
   2 #include <float.h>
   3 #include <stdlib.h>
   4 #include <stdint.h>
   5 #include <stdio.h>
   6
   7 #define check_d1(func, param, expected) \
   8 do { \
   9         int err; hex_union ur; hex_union up; \
  10         double result = func(param); up.f = param; ur.f = result; \
  11         errors += (err = (result != (expected))); \
  12         err \
  13         ? printf("FAIL: %s(%g/"HEXFMT")=%g/"HEXFMT" (expected %g)\n", \
  14                 #func, (double)(param), (long long)up.hex, result, (long long)ur.hex, (double)(expected)) \
  15         : printf("PASS: %s(%g)=%g\n", #func, (double)(param), result); \
  16 } while (0)
  17
  18 #define HEXFMT "%08llx"
  19 typedef union {
  20         double f;
  21         uint64_t hex;
  22 } hex_union;
  23 double result;
  24
  25 #define M_2_SQRT_PIl   3.5449077018110320545963349666822903L   /* 2 sqrt (M_PIl)  */
  26 #define M_SQRT_PIl     1.7724538509055160272981674833411451L   /* sqrt (M_PIl)  */
  27
  28 double zero = 0.0;
  29 double minus_zero = 0.0;
  30 double nan_value = 0.0;
  31 int errors = 0;
  32
  33 int main(void)
  34 {
  35         nan_value /= nan_value;
  36         minus_zero = copysign(zero, -1.0);
  37
  38         //check_d1(tgamma, HUGE_VAL, NAN);
  39         //check_d1(tgamma, negative_integer, NAN);
  40         check_d1(tgamma, 0.0, HUGE_VAL); /* pole */
  41         check_d1(tgamma, minus_zero, -HUGE_VAL); /* pole */
  42         check_d1(tgamma, DBL_MAX/2, HUGE_VAL); /* overflow to inf */
  43         check_d1(tgamma, DBL_MAX, HUGE_VAL); /* overflow to inf */
  44         check_d1(tgamma, HUGE_VAL, HUGE_VAL); /* overflow to inf */
  45         check_d1(tgamma, 7, 2*3*4*5*6); /* normal value */
  46         check_d1(tgamma, -0.5, -M_2_SQRT_PIl); /* normal value (testing negative points) */
  47
  48         check_d1(lgamma, -HUGE_VAL, HUGE_VAL);
  49         //check_d1(lgamma, HUGE_VAL, NAN);
  50         check_d1(lgamma, 0.0, HUGE_VAL); /* pole */
  51         check_d1(lgamma, minus_zero, HUGE_VAL); /* pole */
  52         check_d1(lgamma, 1.0, 0.0);
  53         check_d1(lgamma, 2.0, 0.0);
  54         check_d1(lgamma, DBL_MAX/2, HUGE_VAL); /* overflow to inf */
  55         check_d1(lgamma, DBL_MAX, HUGE_VAL); /* overflow to inf */
  56         check_d1(lgamma, HUGE_VAL, HUGE_VAL); /* overflow to inf */
  57         check_d1(lgamma, 7, log(2*3*4*5*6)); /* normal value */
  58
  59         /* In glibc, gamma == lgamma. (In BSD, it's == tgamma */
  60         check_d1(gamma, -HUGE_VAL, HUGE_VAL);
  61         //check_d1(gamma, HUGE_VAL, NAN);
  62         check_d1(gamma, 0.0, HUGE_VAL); /* pole */
  63         check_d1(gamma, minus_zero, HUGE_VAL); /* pole */
  64         check_d1(gamma, 1.0, 0.0);
  65         check_d1(gamma, 2.0, 0.0);
  66         check_d1(gamma, DBL_MAX/2, HUGE_VAL); /* overflow to inf */
  67         check_d1(gamma, DBL_MAX, HUGE_VAL); /* overflow to inf */
  68         check_d1(gamma, HUGE_VAL, HUGE_VAL); /* overflow to inf */
  69         check_d1(gamma, 7, log(2*3*4*5*6)); /* normal value */
  70
  71         printf("Errors: %d\n", errors);
  72         return errors;
  73 }