--- gforth/float.fs 1994/02/11 16:30:46 1.1 +++ gforth/float.fs 2002/01/17 12:02:55 1.36 @@ -1,28 +1,91 @@ \ High level floating point 14jan94py -: faligned ( addr -- f-addr ) - [ 1 floats 1- ] Literal + [ -1 floats ] Literal and ; +\ Copyright (C) 1995,1997 Free Software Foundation, Inc. -: falign ( -- ) here dup aligned swap - ?DO bl c, LOOP ; +\ This file is part of Gforth. -: f, ( f -- ) here 1 floats allot f! ; - -: fconstant ( r -- ) - Create falign f, - DOES> faligned f@ ; - -: fvariable - Create falign 0 f, - DOES> faligned ; - -: fdepth ( -- n ) f0 @ fp@ - [ 1 floats ] Literal / ; - -: FLit ( -- r ) r> faligned dup f@ float+ >r ; -: FLiteral ( r -- ) postpone FLit falign f, ; immediate - -&16 Value precision -: set-precision to precision ; +\ Gforth 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 +\ of the License, or (at your option) any later version. + +\ This program 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 this program; if not, write to the Free Software +\ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA. + +\ 1 cells 4 = [IF] +\ ' cells Alias sfloats +\ ' cell+ Alias sfloat+ +\ ' align Alias sfalign +\ ' aligned Alias sfaligned +\ [ELSE] +\ : sfloats 2* 2* ; +\ : sfloat+ 4 + ; +\ : sfaligned ( addr -- addr' ) 3 + -4 and ; +\ : sfalign ( -- ) here dup sfaligned swap ?DO bl c, LOOP ; +\ [THEN] + +\ 1 floats 8 = [IF] +\ ' floats Alias dfloats +\ ' float+ Alias dfloat+ +\ ' falign Alias dfalign +\ ' faligned Alias dfaligned +\ [ELSE] +\ : dfloats 2* 2* 2* ; +\ : dfloat+ 8 + ; +\ : dfaligned ( addr -- addr' ) 7 + -8 and ; +\ : dfalign ( -- ) here dup dfaligned swap ?DO bl c, LOOP ; +\ [THEN] + +: sfalign ( -- ) \ float-ext s-f-align + \G If the data-space pointer is not single-float-aligned, reserve + \G enough space to align it. + here dup sfaligned swap ?DO bl c, LOOP ; +: dfalign ( -- ) \ float-ext d-f-align + \G If the data-space pointer is not double-float-aligned, reserve + \G enough space to align it. + here dup dfaligned swap ?DO bl c, LOOP ; + +1 sfloats (Field) sfloat+ , ( sf-addr1 -- sf-addr2 ) \ float-ext s-float-plus +\G @code{1 sfloats +}. + +1 dfloats (Field) dfloat+ , ( df-addr1 -- df-addr2 ) \ float-ext d-float-plus +\G @code{1 dfloats +}. + +: f, ( f -- ) \ gforth + \G Reserve data space for one floating-point number and store + \G @i{f} in the space. + here 1 floats allot f! ; + +: fconstant ( r "name" -- ) \ float f-constant + Create f, +DOES> ( -- r ) + f@ ; + +: fdepth ( -- +n ) \ float f-depth + \G @i{+n} is the current number of (floating-point) values on the + \G floating-point stack. + fp0 @ fp@ - [ 1 floats ] Literal / ; + +: FLit ( -- r ) r> dup f@ float+ >r ; +: FLiteral ( compilation r -- ; run-time -- r ) \ float f-literal + \G Compile appropriate code such that, at run-time, @i{r} is placed + \G on the (floating-point) stack. Interpretation semantics are undefined. + BEGIN here cell+ dup faligned <> WHILE postpone noop REPEAT + postpone FLit f, ; immediate + +&15 Value precision ( -- u ) \ float-ext +\G @i{u} is the number of significant digits currently used by +\G @code{F.} @code{FE.} and @code{FS.} +: set-precision ( u -- ) \ float-ext + \G Set the number of significant digits currently used by + \G @code{F.} @code{FE.} and @code{FS.} to @i{u}. + to precision ; : scratch ( r -- addr len ) pad precision - precision ; @@ -32,29 +95,135 @@ : -zeros ( addr u -- addr' u' ) BEGIN dup WHILE 1- 2dup + c@ '0 <> UNTIL 1+ THEN ; -: f. ( r -- ) scratch represent 0= - IF 2drop scratch 3 min type EXIT THEN - IF '- emit THEN dup >r 0< - IF '0 emit +: f$ ( f -- n ) scratch represent 0= + IF 2drop scratch 3 min type rdrop EXIT THEN + IF '- emit THEN ; + +: f. ( r -- ) \ float-ext f-dot +\G Display (the floating-point number) @i{r} without exponent, +\G followed by a space. + f$ dup >r 0<= + IF '0 emit ELSE scratch r@ min type r@ precision - zeros THEN '. emit r@ negate zeros scratch r> 0 max /string 0 max -zeros type space ; +\ I'm afraid this does not really implement ansi semantics wrt precision. +\ Shouldn't precision indicate the number of places shown after the point? -: fe. ( r -- ) scratch represent 0= - IF 2drop scratch 3 min type EXIT THEN - IF '- emit THEN 1- s>d 3 fm/mod 3 * >r 1+ >r - scratch r@ min type '. emit scratch r> /string type - 'E emit r> . ; +\ Why do you think so? ANS Forth appears ambiguous on this point. -anton. -: fs. ( r -- ) scratch represent 0= - IF 2drop scratch 3 min type EXIT THEN - IF '- emit THEN 1- >r - scratch 1 min type '. emit scratch 1 /string type +: fe. ( r -- ) \ float-ext f-e-dot +\G Display @i{r} using engineering notation (with exponent dividable +\G by 3), followed by a space. + f$ 1- s>d 3 fm/mod 3 * >r 1+ >r + scratch r@ tuck min tuck - >r type r> zeros + '. emit scratch r> /string type 'E emit r> . ; -: fnumber ( string -- r / ) dup count >float 0= - IF defers notfound ELSE drop THEN ; - -' fnumber IS notfound - -1e0 fasin 2e0 f* fconstant pi +: fs. ( r -- ) \ float-ext f-s-dot +\G Display @i{r} using scientific notation (with exponent), followed +\G by a space. + f$ 1- + scratch over c@ emit '. emit 1 /string type + 'E emit . ; + +require debugs.fs + +: sfnumber ( c-addr u -- r true | false ) + 2dup [CHAR] e scan ( c-addr u c-addr2 u2 ) + dup 0= + IF + 2drop 2dup [CHAR] E scan ( c-addr u c-addr3 u3 ) + THEN + nip + IF + >float + ELSE + 2drop false + THEN ; + +:noname ( c-addr u -- ) + 2dup sfnumber + IF + 2drop POSTPONE FLiteral + ELSE + defers compiler-notfound + ENDIF ; +IS compiler-notfound + +:noname ( c-addr u -- r ) + 2dup sfnumber + IF + 2drop + ELSE + defers interpreter-notfound + ENDIF ; +IS interpreter-notfound + +: fvariable ( "name" -- ) \ float f-variable + Create 0.0E0 f, ; + \ does> ( -- f-addr ) + +1.0e0 fasin 2.0e0 f* fconstant pi ( -- r ) \ gforth +\G @code{Fconstant} -- @i{r} is the value pi; the ratio of a circle's area +\G to its diameter. + +: f2* ( r1 -- r2 ) \ gforth + \G Multiply @i{r1} by 2.0e0 + 2.0e0 f* ; + +: f2/ ( r1 -- r2 ) \ gforth + \G Multiply @i{r1} by 0.5e0 + 0.5e0 f* ; + +: 1/f ( r1 -- r2 ) \ gforth + \G Divide 1.0e0 by @i{r1}. + 1.0e0 fswap f/ ; + +get-current environment-wordlist set-current +1.7976931348623157e308 FConstant max-float +set-current + +\ We now have primitives for these, so we need not define them + +\ : falog ( f -- 10^f ) [ 10.0e0 fln ] FLiteral f* fexp ; + +\ : fsinh fexpm1 fdup fdup 1.0e0 f+ f/ f+ f2/ ; +\ : fcosh fexp fdup 1/f f+ f2/ ; +\ : ftanh f2* fexpm1 fdup 2.0e0 f+ f/ ; + +\ : fatanh fdup f0< >r fabs 1.0e0 fover f- f/ f2* flnp1 f2/ +\ r> IF fnegate THEN ; +\ : facosh fdup fdup f* 1.0e0 f- fsqrt f+ fln ; +\ : fasinh fdup fdup f* 1.0e0 f+ fsqrt f/ fatanh ; + +: f~abs ( r1 r2 r3 -- flag ) \ gforth + \G Approximate equality with absolute error: |r1-r2|0: + \G @code{f~abs}; r3=0: bitwise comparison; r3<0: @code{fnegate f~rel}. + fdup f0= + IF \ bitwise comparison + fp@ float+ 1 floats over float+ -text 0= + fdrop fdrop fdrop + EXIT + THEN + fdup f0> + IF + f~abs + ELSE + fnegate f~rel + THEN ; + +: f.s ( -- ) \ gforth f-dot-s + \G Display the number of items on the floating-point stack, + \G followed by a list of the items; TOS is the right-most item. + ." <" fdepth 0 .r ." > " fdepth 0 max maxdepth-.s @ min dup 0 + ?DO dup i - 1- floats fp@ + f@ f. LOOP drop ;