File:  [gforth] / gforth / float.fs
Revision 1.22: download - view: text, annotated - select for diffs
Sun Jul 6 16:00:11 1997 UTC (22 years, 3 months ago) by jwilke
Branches: MAIN
CVS tags: HEAD
Changed f0 to fp0.
jens

    1: \ High level floating point                            14jan94py
    2: 
    3: \ Copyright (C) 1995 Free Software Foundation, Inc.
    4: 
    5: \ This file is part of Gforth.
    6: 
    7: \ Gforth is free software; you can redistribute it and/or
    8: \ modify it under the terms of the GNU General Public License
    9: \ as published by the Free Software Foundation; either version 2
   10: \ of the License, or (at your option) any later version.
   11: 
   12: \ This program is distributed in the hope that it will be useful,
   13: \ but WITHOUT ANY WARRANTY; without even the implied warranty of
   14: \ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   15: \ GNU General Public License for more details.
   16: 
   17: \ You should have received a copy of the GNU General Public License
   18: \ along with this program; if not, write to the Free Software
   19: \ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
   20: 
   21: \ 1 cells 4 = [IF]
   22: \ ' cells   Alias sfloats
   23: \ ' cell+   Alias sfloat+
   24: \ ' align   Alias sfalign
   25: \ ' aligned Alias sfaligned
   26: \ [ELSE]
   27: \ : sfloats  2* 2* ;
   28: \ : sfloat+  4 + ;
   29: \ : sfaligned ( addr -- addr' )  3 + -4 and ;
   30: \ : sfalign ( -- )  here dup sfaligned swap ?DO  bl c,  LOOP ;
   31: \ [THEN]
   32: 
   33: \ 1 floats 8 = [IF]
   34: \ ' floats   Alias dfloats
   35: \ ' float+   Alias dfloat+
   36: \ ' falign   Alias dfalign
   37: \ ' faligned Alias dfaligned
   38: \ [ELSE]
   39: \ : dfloats  2* 2* 2* ;
   40: \ : dfloat+  8 + ;
   41: \ : dfaligned ( addr -- addr' )  7 + -8 and ;
   42: \ : dfalign ( -- )  here dup dfaligned swap ?DO  bl c,  LOOP ;
   43: \ [THEN]
   44: 
   45: : sfalign ( -- ) \ float-ext s-f-align
   46:     here dup sfaligned swap ?DO  bl c,  LOOP ;
   47: : dfalign ( -- ) \ float-ext d-f-align
   48:     here dup dfaligned swap ?DO  bl c,  LOOP ;
   49: 
   50: 1 sfloats constant sfloat+ ( sf-addr1 -- sf-addr2 ) \ float-ext s-float-plus
   51: dofield: lastxt code-address! \ change the constant into a field
   52: 
   53: 1 dfloats constant dfloat+ ( df-addr1 -- df-addr2 ) \ float-ext d-float-plus
   54: dofield: lastxt code-address! \ change the constant into a field
   55: 
   56: : f, ( f -- )  here 1 floats allot f! ;
   57: 
   58: : fconstant  ( r "name" -- ) \ float
   59:     Create f,
   60: DOES> ( -- r )
   61:     f@ ;
   62: 
   63: : fdepth  ( -- n )  fp0 @ fp@ - [ 1 floats ] Literal / ;
   64: 
   65: : FLit ( -- r )  r> dup f@ float+ >r ;
   66: : FLiteral ( r -- )
   67:   BEGIN  here cell+ dup faligned <>  WHILE  postpone noop  REPEAT
   68:   postpone FLit  f, ;  immediate
   69: 
   70: &15 Value precision
   71: : set-precision  to precision ;
   72: 
   73: : scratch ( r -- addr len )
   74:   pad precision - precision ;
   75: 
   76: : zeros ( n -- )   0 max 0 ?DO  '0 emit  LOOP ;
   77: 
   78: : -zeros ( addr u -- addr' u' )
   79:   BEGIN  dup  WHILE  1- 2dup + c@ '0 <>  UNTIL  1+  THEN ;
   80: 
   81: : f$ ( f -- n )  scratch represent 0=
   82:   IF  2drop  scratch 3 min type  rdrop  EXIT  THEN
   83:   IF  '- emit  THEN ;
   84: 
   85: : f.  ( r -- )  f$ dup >r 0<
   86:   IF    '0 emit
   87:   ELSE  scratch r@ min type  r@ precision - zeros  THEN
   88:   '. emit r@ negate zeros
   89:   scratch r> 0 max /string 0 max -zeros type space ;
   90: \ I'm afraid this does not really implement ansi semantics wrt precision.
   91: \ Shouldn't precision indicate the number of places shown after the point?
   92: 
   93: : fe. ( r -- )  f$ 1- s>d 3 fm/mod 3 * >r 1+ >r
   94:   scratch r@ min type '. emit  scratch r> /string type
   95:   'E emit r> . ;
   96: 
   97: : fs. ( r -- )  f$ 1-
   98:   scratch over c@ emit '. emit 1 /string type
   99:   'E emit . ;
  100: 
  101: require debugs.fs
  102: 
  103: : sfnumber ( c-addr u -- r true | false )
  104:     2dup [CHAR] e scan ( c-addr u c-addr2 u2 )
  105:     dup 0=
  106:     IF
  107: 	2drop 2dup [CHAR] E scan ( c-addr u c-addr3 u3 )
  108:     THEN
  109:     nip
  110:     IF
  111: 	>float
  112:     ELSE
  113: 	2drop false
  114:     THEN ;
  115: 
  116: :noname ( c-addr u -- )
  117:     2dup sfnumber
  118:     IF
  119: 	2drop POSTPONE FLiteral
  120:     ELSE
  121: 	defers compiler-notfound
  122:     ENDIF ;
  123: IS compiler-notfound
  124: 
  125: :noname ( c-addr u -- r )
  126:     2dup sfnumber
  127:     IF
  128: 	2drop
  129:     ELSE
  130: 	defers interpreter-notfound
  131:     ENDIF ;
  132: IS interpreter-notfound
  133: 
  134: : fvariable ( "name" -- ) \ float
  135:     Create 0.0E0 f, ;
  136:     \ does> ( -- f-addr )
  137: 
  138: 1.0e0 fasin 2.0e0 f* fconstant pi
  139: 
  140: : f2*  2.0e0 f* ;
  141: : f2/  0.5e0 f* ;
  142: : 1/f  1.0e0 fswap f/ ;
  143: 
  144: 
  145: \ We now have primitives for these, so we need not define them
  146: 
  147: \ : falog ( f -- 10^f )  [ 10.0e0 fln ] FLiteral f* fexp ;
  148: 
  149: \ : fsinh    fexpm1 fdup fdup 1.0e0 f+ f/ f+ f2/ ;
  150: \ : fcosh    fexp fdup 1/f f+ f2/ ;
  151: \ : ftanh    f2* fexpm1 fdup 2.0e0 f+ f/ ;
  152: 
  153: \ : fatanh   fdup f0< >r fabs 1.0e0 fover f- f/  f2* flnp1 f2/
  154: \            r> IF  fnegate  THEN ;
  155: \ : facosh   fdup fdup f* 1.0e0 f- fsqrt f+ fln ;
  156: \ : fasinh   fdup fdup f* 1.0e0 f+ fsqrt f/ fatanh ;
  157: 
  158: \ !! factor out parts
  159: : f~ ( f1 f2 f3 -- flag ) \ float-ext
  160:     fdup f0=
  161:     IF
  162: 	fdrop f= EXIT
  163:     THEN
  164:     fdup f0>
  165:     IF
  166: 	frot frot f- fabs fswap
  167:     ELSE
  168: 	fnegate frot frot fover fabs fover fabs f+ frot frot
  169: 	f- fabs frot frot f*
  170:     THEN
  171:     f< ;
  172: 
  173: : f.s  ." <" fdepth 0 .r ." > " fdepth 0 max maxdepth-.s @ min dup 0 
  174:   ?DO  dup i - 1- floats fp@ + f@ f.  LOOP  drop ; 

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