sinh.cpp

   1 //                exp(x) - exp(-x)
   2 //      sinh(x) = ----------------
   3 //                       2
   4
   5 #include "stdafx.h"
   6 #include "defs.h"
   7
   8 void
   9 eval_sinh(void)
  10 {
  11         push(cadr(p1));
  12         eval();
  13         ysinh();
  14 }
  15
  16 void
  17 ysinh(void)
  18 {
  19         save();
  20         yysinh();
  21         restore();
  22 }
  23
  24 void
  25 yysinh(void)
  26 {
  27         double d;
  28         p1 = pop();
  29         if (car(p1) == symbol(ARCSINH)) {
  30                 push(cadr(p1));
  31                 return;
  32         }
  33         if (isdouble(p1)) {
  34                 d = sinh(p1->u.d);
  35                 if (fabs(d) < 1e-10)
  36                         d = 0.0;
  37                 push_double(d);
  38                 return;
  39         }
  40         if (iszero(p1)) {
  41                 push(zero);
  42                 return;
  43         }
  44         push_symbol(SINH);
  45         push(p1);
  46         list(2);
  47 }
  48
  49 #if SELFTEST
  50
  51 static char *s[] = {
  52
  53         "sinh(x)",
  54         "sinh(x)",
  55
  56         "sinh(0)",
  57         "0",
  58
  59         "sinh(arcsinh(x))",
  60         "x",
  61 };
  62
  63 void
  64 test_sinh(void)
  65 {
  66         test(__FILE__, s, sizeof s / sizeof (char *));
  67 }
  68
  69 #endif