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comparison src/floatfns.c @ 4931:8a08cf0b7583

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merge
author Ben Wing <ben@xemacs.org>
date Thu, 21 Jan 2010 00:46:37 -0600
parents 6c0bb4d2c23a
children 6ef8256a020a 19a72041c5ed
comparison
equal deleted inserted replaced
4930:9f04877ce07e 4931:8a08cf0b7583
24 acos, asin, atan, atan2, ceil, cos, cosh, exp, fabs, floor, fmod, 24 acos, asin, atan, atan2, ceil, cos, cosh, exp, fabs, floor, fmod,
25 frexp, ldexp, log, log10, modf, pow, sin, sinh, sqrt, tan, tanh. 25 frexp, ldexp, log, log10, modf, pow, sin, sinh, sqrt, tan, tanh.
26 26
27 Define HAVE_INVERSE_HYPERBOLIC if you have acosh, asinh, and atanh. 27 Define HAVE_INVERSE_HYPERBOLIC if you have acosh, asinh, and atanh.
28 Define HAVE_CBRT if you have cbrt(). 28 Define HAVE_CBRT if you have cbrt().
29 Define HAVE_RINT if you have rint().
30 If you don't define these, then the appropriate routines will be simulated. 29 If you don't define these, then the appropriate routines will be simulated.
31 30
32 Define HAVE_MATHERR if on a system supporting the SysV matherr() callback. 31 Define HAVE_MATHERR if on a system supporting the SysV matherr() callback.
33 (This should happen automatically.) 32 (This should happen automatically.)
34 33
48 #include <config.h> 47 #include <config.h>
49 #include "lisp.h" 48 #include "lisp.h"
50 #include "syssignal.h" 49 #include "syssignal.h"
51 #include "sysfloat.h" 50 #include "sysfloat.h"
52 51
53 /* The code uses emacs_rint, so that it works to undefine HAVE_RINT 52 /* An implementation of rint that always rounds towards the even number in
54 if `rint' exists but does not work right. */ 53 the case of ambiguity. */
55 #ifdef HAVE_RINT
56 #define emacs_rint rint
57 #else
58 static double 54 static double
59 emacs_rint (double x) 55 emacs_rint (double x)
60 { 56 {
61 double r = floor (x + 0.5); 57 double r = floor (x + 0.5);
62 double diff = fabs (r - x); 58 double diff = fabs (r - x);
63 /* Round to even and correct for any roundoff errors. */ 59 /* Round to even and correct for any roundoff errors. */
64 if (diff >= 0.5 && (diff > 0.5 || r != 2.0 * floor (r / 2.0))) 60 if (diff >= 0.5 && (diff > 0.5 || r != 2.0 * floor (r / 2.0)))
65 r += r < x ? 1.0 : -1.0; 61 r += r < x ? 1.0 : -1.0;
66 return r; 62 return r;
67 } 63 }
68 #endif
69 64
70 /* Nonzero while executing in floating point. 65 /* Nonzero while executing in floating point.
71 This tells float_error what to do. */ 66 This tells float_error what to do. */
72 static int in_float; 67 static int in_float;
73 68