--- gforth/float.fs 1997/07/06 16:00:11 1.22 +++ gforth/float.fs 1999/02/03 00:10:20 1.24 @@ -1,6 +1,6 @@ \ High level floating point 14jan94py -\ Copyright (C) 1995 Free Software Foundation, Inc. +\ Copyright (C) 1995,1997 Free Software Foundation, Inc. \ This file is part of Gforth. @@ -60,15 +60,25 @@ dofield: lastxt code-address! \ change t DOES> ( -- r ) f@ ; -: fdepth ( -- n ) fp0 @ fp@ - [ 1 floats ] Literal / ; +: fdepth ( -- +n ) \ floating f-depth + \G +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 ( r -- ) - BEGIN here cell+ dup faligned <> WHILE postpone noop REPEAT - postpone FLit f, ; immediate - -&15 Value precision -: set-precision to precision ; +: FLiteral ( compilation r -- ; run-time -- r ) \ float + \G Compile appropriate code such that, at run-time, 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 ) \ floating-ext +\G u is the number of significant digits currently used by +\G @code{F.} @code{FE.} and @code{FS.} +: set-precision ( u -- ) \ floating-ext + \G Set the number of significant digits currently used by + \G @code{F.} @code{FE.} and @code{FS.} to u. + to precision ; : scratch ( r -- addr len ) pad precision - precision ; @@ -82,7 +92,10 @@ DOES> ( -- r ) IF 2drop scratch 3 min type rdrop EXIT THEN IF '- emit THEN ; -: f. ( r -- ) f\$ dup >r 0< +: f. ( r -- ) \ floating-ext f-dot +\G Display (the floating-point number) r using fixed-point notation, +\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 @@ -90,11 +103,15 @@ DOES> ( -- r ) \ 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 -- ) f\$ 1- s>d 3 fm/mod 3 * >r 1+ >r +: fe. ( r -- ) \ floating-ext f-e-dot +\G Display r using engineering notation, followed by a space. + f\$ 1- s>d 3 fm/mod 3 * >r 1+ >r scratch r@ min type '. emit scratch r> /string type 'E emit r> . ; -: fs. ( r -- ) f\$ 1- +: fs. ( r -- ) \ floating-ext f-s-dot +\G Display r using scientific notation, followed by a space. + f\$ 1- scratch over c@ emit '. emit 1 /string type 'E emit . ; @@ -135,11 +152,21 @@ IS interpreter-notfound Create 0.0E0 f, ; \ does> ( -- f-addr ) -1.0e0 fasin 2.0e0 f* fconstant pi - -: f2* 2.0e0 f* ; -: f2/ 0.5e0 f* ; -: 1/f 1.0e0 fswap f/ ; +1.0e0 fasin 2.0e0 f* fconstant pi ( -- r ) \ gforth +\G FCONSTANT: r is the value pi; the ratio of a circle's area +\G to its diameter. + +: f2* ( r1 -- r2 ) \ gforth + \G Multiply r1 by 2.0e0 + 2.0e0 f* ; + +: f2/ ( r1 -- r2 ) \ gforth + \G Multiply r1 by 0.5e0 + 0.5e0 f* ; + +: 1/f ( r1 -- r2 ) \ gforth + \G Divide 1.0e0 by r1 + 1.0e0 fswap f/ ; \ We now have primitives for these, so we need not define them @@ -170,5 +197,8 @@ IS interpreter-notfound THEN f< ; -: f.s ." <" fdepth 0 .r ." > " fdepth 0 max maxdepth-.s @ min dup 0 - ?DO dup i - 1- floats fp@ + f@ f. LOOP drop ; +: 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 ;