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- /* Primitive operations on floating point for GNU Emacs Lisp interpreter.
- Copyright (C) 1988-1993 Free Software Foundation, Inc.
-
- This file is part of GNU Emacs.
-
- GNU Emacs is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2, or (at your option)
- any later version.
-
- GNU Emacs is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with GNU Emacs; see the file COPYING. If not, write to
- the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
-
- /* ANSI C requires only these float functions:
- acos, asin, atan, atan2, ceil, cos, cosh, exp, fabs, floor, fmod,
- frexp, ldexp, log, log10, modf, pow, sin, sinh, sqrt, tan, tanh.
-
- Define HAVE_INVERSE_HYPERBOLIC if you have acosh, asinh, and atanh.
- Define HAVE_CBRT if you have cbrt().
- Define HAVE_RINT if you have rint().
- If you don't define these, then the appropriate routines will be simulated.
-
- Define HAVE_MATHERR if on a system supporting the SysV matherr() callback.
- (This should happen automatically.)
-
- Define FLOAT_CHECK_ERRNO if the float library routines set errno.
- This has no effect if HAVE_MATHERR is defined.
-
- Define FLOAT_CATCH_SIGILL if the float library routines signal SIGILL.
- (What systems actually do this? Let me know. -jwz)
-
- Define FLOAT_CHECK_DOMAIN if the float library doesn't handle errors by
- either setting errno, or signalling SIGFPE/SIGILL. Otherwise, domain and
- range checking will happen before calling the float routines. This has
- no effect if HAVE_MATHERR is defined (since matherr will be called when
- a domain error occurs.)
- */
-
- #include <signal.h>
-
- #include "config.h"
- #include "lisp.h"
-
- #ifdef LISP_FLOAT_TYPE
-
- #include <math.h>
-
- #if defined(DOMAIN) && defined(SING) && defined(OVERFLOW)
- /* If those are defined, then this is probably a `matherr' machine. */
- # ifndef HAVE_MATHERR
- # define HAVE_MATHERR
- # endif
- #endif
-
- #ifdef HAVE_MATHERR
- # ifdef FLOAT_CHECK_ERRNO
- # undef FLOAT_CHECK_ERRNO
- # endif
- # ifdef FLOAT_CHECK_DOMAIN
- # undef FLOAT_CHECK_DOMAIN
- # endif
- #endif
-
- #ifdef FLOAT_CHECK_ERRNO
- # include <errno.h>
- #endif
-
- extern Lisp_Object Qarith_error, Qrange_error, Qdomain_error;
- extern Lisp_Object Qsingularity_error, Qoverflow_error, Qunderflow_error;
-
- /* Nonzero while executing in floating point.
- This tells float_error what to do. */
- static int in_float;
-
- #ifdef FLOAT_CHECK_ERRNO
- #define IN_FLOAT(d) \
- do { \
- in_float = 1; errno = 0; (d); in_float = 0; \
- switch (errno) { \
- case 0: break; \
- case EDOM: Fsignal (Qdomain_error, Qnil); break; \
- case ERANGE: Fsignal (Qrange_error, Qnil); break; \
- default: Fsignal (Qarith_error, Qnil); break; \
- } \
- } while (0)
- #else
- #define IN_FLOAT(d) (in_float = 1, (d), in_float = 0)
- #endif
-
- #ifndef HAVE_RINT
- #define rint(x) (floor((x)+0.5))
- #endif
-
- #define range_error(op,arg) \
- Fsignal (Qrange_error, list2 (build_string ((op)), (arg)))
- #define domain_error(op,arg) \
- Fsignal (Qdomain_error, list2 (build_string ((op)), (arg)))
- #define domain_error2(op,a1,a2) \
- Fsignal (Qdomain_error, list3 (build_string ((op)), (a1), (a2)))
-
- /* Extract a Lisp number as a `double', or signal an error. */
-
- double
- extract_float (arg)
- Lisp_Object arg;
- {
- CHECK_NUMBER (arg, 0);
-
- if (FLOATP (arg))
- return XFLOAT (arg)->data;
- return (double) XINT (arg);
- }
-
- DEFUN ("acos", Facos, Sacos, 1, 1, 0,
- "Return the inverse cosine of ARG.")
- (arg)
- register Lisp_Object arg;
- {
- double d = extract_float (arg);
- #ifdef FLOAT_CHECK_DOMAIN
- if (d > 1.0 || d < -1.0)
- domain_error ("acos", arg);
- #endif
- IN_FLOAT (d = acos (d));
- return make_float (d);
- }
-
- DEFUN ("acosh", Facosh, Sacosh, 1, 1, 0,
- "Return the inverse hyperbolic cosine of ARG.")
- (arg)
- register Lisp_Object arg;
- {
- double d = extract_float (arg);
- #ifdef FLOAT_CHECK_DOMAIN
- if (d < 1.0)
- domain_error ("acosh", arg);
- #endif
- #ifdef HAVE_INVERSE_HYPERBOLIC
- IN_FLOAT (d = acosh (d));
- #else
- IN_FLOAT (d = log (d + sqrt (d*d - 1.0)));
- #endif
- return make_float (d);
- }
-
- DEFUN ("asin", Fasin, Sasin, 1, 1, 0,
- "Return the inverse sine of ARG.")
- (arg)
- register Lisp_Object arg;
- {
- double d = extract_float (arg);
- #ifdef FLOAT_CHECK_DOMAIN
- if (d > 1.0 || d < -1.0)
- domain_error ("asin", arg);
- #endif
- IN_FLOAT (d = asin (d));
- return make_float (d);
- }
-
- DEFUN ("asinh", Fasinh, Sasinh, 1, 1, 0,
- "Return the inverse hyperbolic sine of ARG.")
- (arg)
- register Lisp_Object arg;
- {
- double d = extract_float (arg);
- #ifdef HAVE_INVERSE_HYPERBOLIC
- IN_FLOAT (d = asinh (d));
- #else
- IN_FLOAT (d = log (d + sqrt (d*d + 1.0)));
- #endif
- return make_float (d);
- }
-
- DEFUN ("atan", Fatan, Satan, 1, 2, 0,
- "Return the inverse tangent of ARG.")
- (arg1, arg2)
- register Lisp_Object arg1, arg2;
- {
- double d = extract_float (arg1);
- if (NILP (arg2))
- IN_FLOAT (d = atan (d));
- else
- {
- double d2 = extract_float (arg2);
- #ifdef FLOAT_CHECK_DOMAIN
- if (d == 0.0 && d2 == 0.0)
- domain_error2 ("atan", arg1, arg2);
- #endif
- IN_FLOAT (d = atan2 (d, d2));
- }
- return make_float (d);
- }
-
- DEFUN ("atanh", Fatanh, Satanh, 1, 1, 0,
- "Return the inverse hyperbolic tangent of ARG.")
- (arg)
- register Lisp_Object arg;
- {
- double d = extract_float (arg);
- #ifdef FLOAT_CHECK_DOMAIN
- if (d >= 1.0 || d <= -1.0)
- domain_error ("atanh", arg);
- #endif
- #ifdef HAVE_INVERSE_HYPERBOLIC
- IN_FLOAT (d = atanh (d));
- #else
- IN_FLOAT (d = 0.5 * log ((1.0 + d) / (1.0 - d)));
- #endif
- return make_float (d);
- }
-
- DEFUN ("cos", Fcos, Scos, 1, 1, 0,
- "Return the cosine of ARG.")
- (arg)
- register Lisp_Object arg;
- {
- double d = extract_float (arg);
- IN_FLOAT (d = cos (d));
- return make_float (d);
- }
-
- DEFUN ("cosh", Fcosh, Scosh, 1, 1, 0,
- "Return the hyperbolic cosine of ARG.")
- (arg)
- register Lisp_Object arg;
- {
- double d = extract_float (arg);
- #ifdef FLOAT_CHECK_DOMAIN
- if (d > 710.0 || d < -710.0)
- range_error ("cosh", arg);
- #endif
- IN_FLOAT (d = cosh (d));
- return make_float (d);
- }
-
- DEFUN ("cube-root", Fcube_root, Scube_root, 1, 1, 0,
- "Return the cube root of ARG.")
- (arg)
- register Lisp_Object arg;
- {
- double d = extract_float (arg);
- #ifdef HAVE_CBRT
- IN_FLOAT (d = cbrt (d));
- #else
- if (d >= 0.0)
- IN_FLOAT (d = pow (d, 1.0/3.0));
- else
- IN_FLOAT (d = -pow (-d, 1.0/3.0));
- #endif
- return make_float (d);
- }
-
- DEFUN ("exp", Fexp, Sexp, 1, 1, 0,
- "Return the exponential base e of ARG.")
- (arg)
- register Lisp_Object arg;
- {
- double d = extract_float (arg);
- #ifdef FLOAT_CHECK_DOMAIN
- if (d > 709.7827) /* Assume IEEE doubles here */
- range_error ("exp", arg);
- else if (d < -709.0)
- return make_float (0.0);
- else
- #endif
- IN_FLOAT (d = exp (d));
- return make_float (d);
- }
-
- DEFUN ("log", Flog, Slog, 1, 2, 0,
- "Return the natural logarithm of ARG.\n\
- With two arguments, return the logarithm of ARG to the base ARG2.")
- (arg1, arg2)
- register Lisp_Object arg1, arg2;
- {
- double d = extract_float (arg1);
- #ifdef FLOAT_CHECK_DOMAIN
- if (d <= 0.0)
- domain_error2 ("log", arg1, arg2);
- #endif
- if (NILP (arg2))
- IN_FLOAT (d = log (d));
- else
- {
- double d2 = extract_float (arg2);
- #ifdef FLOAT_CHECK_DOMAIN
- if (d2 <= 0.0 || d2 == 1.0)
- domain_error2 ("log", arg1, arg2);
- #endif
- if (d2 == 10.0)
- IN_FLOAT (d = log10 (d));
- else
- IN_FLOAT (d = log (d) / log (d2));
- }
- return make_float (d);
- }
-
- DEFUN ("log10", Flog10, Slog10, 1, 1, 0,
- "Return the logarithm base 10 of ARG.")
- (arg)
- register Lisp_Object arg;
- {
- double d = extract_float (arg);
- #ifdef FLOAT_CHECK_DOMAIN
- if (d <= 0.0)
- domain_error ("log10", arg);
- #endif
- IN_FLOAT (d = log10 (d));
- return make_float (d);
- }
-
- DEFUN ("expt", Fexpt, Sexpt, 2, 2, 0,
- "Return the exponential x ** y.")
- (arg1, arg2)
- register Lisp_Object arg1, arg2;
- {
- double f1, f2;
-
- CHECK_NUMBER (arg1, 0);
- CHECK_NUMBER (arg2, 0);
- if ((FIXNUMP (arg1)) && /* common lisp spec */
- (FIXNUMP (arg2))) /* don't promote, if both are ints */
- {
- int acc, x, y;
- x = XINT (arg1);
- y = XINT (arg2);
-
- if (y < 0)
- {
- if (x == 1)
- acc = 1;
- else if (x == -1)
- acc = (y & 1) ? -1 : 1;
- else
- acc = 0;
- }
- else
- {
- acc = 1;
- while (y > 0)
- {
- if (y & 1)
- acc *= x;
- x *= x;
- y = (unsigned)y >> 1;
- }
- }
- return XSET (x, Lisp_Int, acc);
- }
- f1 = (FLOATP (arg1)) ? XFLOAT (arg1)->data : XINT (arg1);
- f2 = (FLOATP (arg2)) ? XFLOAT (arg2)->data : XINT (arg2);
- /* Really should check for overflow, too */
- if (f1 == 0.0 && f2 == 0.0)
- f1 = 1.0;
- #ifdef FLOAT_CHECK_DOMAIN
- else if ((f1 == 0.0 && f2 < 0.0) || (f1 < 0 && f2 != floor(f2)))
- domain_error2 ("pow", arg1, arg2);
- #endif
- IN_FLOAT (f1 = pow (f1, f2));
- return make_float (f1);
- }
-
- DEFUN ("sin", Fsin, Ssin, 1, 1, 0,
- "Return the sine of ARG.")
- (arg)
- register Lisp_Object arg;
- {
- double d = extract_float (arg);
- IN_FLOAT (d = sin (d));
- return make_float (d);
- }
-
- DEFUN ("sinh", Fsinh, Ssinh, 1, 1, 0,
- "Return the hyperbolic sine of ARG.")
- (arg)
- register Lisp_Object arg;
- {
- double d = extract_float (arg);
- #ifdef FLOAT_CHECK_DOMAIN
- if (d > 710.0 || d < -710.0)
- range_error ("sinh", arg);
- #endif
- IN_FLOAT (d = sinh (d));
- return make_float (d);
- }
-
- DEFUN ("sqrt", Fsqrt, Ssqrt, 1, 1, 0,
- "Return the square root of ARG.")
- (arg)
- register Lisp_Object arg;
- {
- double d = extract_float (arg);
- #ifdef FLOAT_CHECK_DOMAIN
- if (d < 0.0)
- domain_error ("sqrt", arg);
- #endif
- IN_FLOAT (d = sqrt (d));
- return make_float (d);
- }
-
- DEFUN ("tan", Ftan, Stan, 1, 1, 0,
- "Return the tangent of ARG.")
- (arg)
- register Lisp_Object arg;
- {
- double d = extract_float (arg);
- double c = cos (d);
- #ifdef FLOAT_CHECK_DOMAIN
- if (c == 0.0)
- domain_error ("tan", arg);
- #endif
- IN_FLOAT (d = sin (d) / c);
- return make_float (d);
- }
-
- DEFUN ("tanh", Ftanh, Stanh, 1, 1, 0,
- "Return the hyperbolic tangent of ARG.")
- (arg)
- register Lisp_Object arg;
- {
- double d = extract_float (arg);
- IN_FLOAT (d = tanh (d));
- return make_float (d);
- }
-
- DEFUN ("abs", Fabs, Sabs, 1, 1, 0,
- "Return the absolute value of ARG.")
- (arg)
- register Lisp_Object arg;
- {
- CHECK_NUMBER (arg, 0);
-
- if (FLOATP (arg))
- IN_FLOAT (arg = make_float ((double) fabs (XFLOAT (arg)->data)));
- else if (XINT (arg) < 0)
- XSETINT (arg, - XFASTINT (arg));
-
- return arg;
- }
-
- DEFUN ("float", Ffloat, Sfloat, 1, 1, 0,
- "Return the floating point number equal to ARG.")
- (arg)
- register Lisp_Object arg;
- {
- CHECK_NUMBER (arg, 0);
-
- if (FIXNUMP (arg))
- return make_float ((double) XINT (arg));
- else /* give 'em the same float back */
- return arg;
- }
-
- /* the rounding functions */
-
- DEFUN ("ceiling", Fceiling, Sceiling, 1, 1, 0,
- "Return the smallest integer no less than ARG. (Round toward +inf.)")
- (arg)
- register Lisp_Object arg;
- {
- CHECK_NUMBER (arg, 0);
-
- if (FLOATP (arg))
- IN_FLOAT (XSET (arg, Lisp_Int, ceil (XFLOAT (arg)->data)));
-
- return arg;
- }
-
- DEFUN ("floor", Ffloor, Sfloor, 1, 1, 0,
- "Return the largest integer no greater than ARG. (Round towards -inf.)")
- (arg)
- register Lisp_Object arg;
- {
- CHECK_NUMBER (arg, 0);
-
- if (FLOATP (arg))
- IN_FLOAT (XSET (arg, Lisp_Int, floor (XFLOAT (arg)->data)));
-
- return arg;
- }
-
- DEFUN ("round", Fround, Sround, 1, 1, 0,
- "Return the nearest integer to ARG.")
- (arg)
- register Lisp_Object arg;
- {
- CHECK_NUMBER (arg, 0);
-
- if (FLOATP (arg))
- IN_FLOAT (XSET (arg, Lisp_Int, rint (XFLOAT (arg)->data)));
-
- return arg;
- }
-
- DEFUN ("truncate", Ftruncate, Struncate, 1, 1, 0,
- "Truncate a floating point number to an int.\n\
- Rounds the value toward zero.")
- (arg)
- register Lisp_Object arg;
- {
- CHECK_NUMBER (arg, 0);
-
- if (FLOATP (arg))
- XSET (arg, Lisp_Int, (int) XFLOAT (arg)->data);
-
- return arg;
- }
-
- DEFUN ("fceiling", Ffceiling, Sfceiling, 1, 1, 0,
- "Return the smallest integer no less than ARG, as a float.\n\
- \(Round toward +inf.\)")
- (arg)
- register Lisp_Object arg;
- {
- double d = extract_float (arg);
- IN_FLOAT (d = ceil (d));
- return make_float (d);
- }
-
- DEFUN ("ffloor", Fffloor, Sffloor, 1, 1, 0,
- "Return the largest integer no greater than ARG, as a float.\n\
- \(Round towards -inf.\)")
- (arg)
- register Lisp_Object arg;
- {
- double d = extract_float (arg);
- IN_FLOAT (d = floor (d));
- return make_float (d);
- }
-
- DEFUN ("fround", Ffround, Sfround, 1, 1, 0,
- "Return the nearest integer to ARG, as a float.")
- (arg)
- register Lisp_Object arg;
- {
- double d = extract_float (arg);
- IN_FLOAT (d = rint (d));
- return make_float (d);
- }
-
- DEFUN ("ftruncate", Fftruncate, Sftruncate, 1, 1, 0,
- "Truncate a floating point number to an integral float value.\n\
- Rounds the value toward zero.")
- (arg)
- register Lisp_Object arg;
- {
- double d = extract_float (arg);
- if (d >= 0.0)
- IN_FLOAT (d = floor (d));
- else
- IN_FLOAT (d = ceil (d));
- return make_float (d);
- }
-
- #ifdef FLOAT_CATCH_SIGILL
- static void
- float_error (signo)
- int signo;
- {
- if (! in_float)
- fatal_error_signal (signo);
-
- #ifdef BSD4_1
- sigrelse (SIGILL);
- #else /* not BSD4_1 */
- sigsetmask (0);
- #endif /* not BSD4_1 */
-
- in_float = 0;
-
- Fsignal (Qarith_error, Qnil);
- }
-
- /* Another idea was to replace the library function `infnan'
- where SIGILL is signaled. */
-
- #endif /* FLOAT_CATCH_SIGILL */
-
- #ifdef HAVE_MATHERR
- int
- matherr (x)
- struct exception *x;
- {
- Lisp_Object args;
- if (! in_float)
- /* Not called from emacs-lisp float routines; do the default thing. */
- return 0;
- args =
- Fcons (build_string (x->name),
- Fcons (make_float (x->arg1),
- ((!strcmp (x->name, "log") || !strcmp (x->name, "pow"))
- ? Fcons (make_float (x->arg2), Qnil)
- : Qnil)));
- switch (x->type)
- {
- case DOMAIN: Fsignal (Qdomain_error, args); break;
- case SING: Fsignal (Qsingularity_error, args); break;
- case OVERFLOW: Fsignal (Qoverflow_error, args); break;
- case UNDERFLOW: Fsignal (Qunderflow_error, args); break;
- default: Fsignal (Qarith_error, args); break;
- }
- return (1); /* don't set errno or print a message */
- }
- #endif /* HAVE_MATHERR */
-
- void
- init_floatfns ()
- {
- #ifdef FLOAT_CATCH_SIGILL
- signal (SIGILL, float_error);
- #endif
- in_float = 0;
- }
-
- void
- syms_of_floatfns ()
- {
- defsubr (&Sacos);
- defsubr (&Sacosh);
- defsubr (&Sasin);
- defsubr (&Sasinh);
- defsubr (&Satan);
- defsubr (&Satanh);
- defsubr (&Scos);
- defsubr (&Scosh);
- defsubr (&Scube_root);
- defsubr (&Sexp);
- defsubr (&Slog);
- defsubr (&Slog10);
- defsubr (&Sexpt);
- defsubr (&Ssin);
- defsubr (&Ssinh);
- defsubr (&Ssqrt);
- defsubr (&Stan);
- defsubr (&Stanh);
-
- defsubr (&Sabs);
- defsubr (&Sfloat);
- defsubr (&Sceiling);
- defsubr (&Sfloor);
- defsubr (&Sround);
- defsubr (&Struncate);
- defsubr (&Sfceiling);
- defsubr (&Sffloor);
- defsubr (&Sfround);
- defsubr (&Sftruncate);
- }
-
- #else /* not LISP_FLOAT_TYPE */
-
- init_floatfns ()
- {}
-
- syms_of_floatfns ()
- {}
-
- #endif /* not LISP_FLOAT_TYPE */
-