Node:Floating point stack, Next:Return stack, Previous:Data stack, Up:Stack Manipulation
Whilst every sane Forth has a separate floating-point stack, it is not
strictly required; an ANS Forth system could theoretically keep
floating-point numbers on the data stack. As an additional difficulty,
you don't know how many cells a floating-point number takes. It is
reportedly possible to write words in a way that they work also for a
unified stack model, but we do not recommend trying it. Instead, just
say that your program has an environmental dependency on a separate
floating-point stack.
floating-stack       -- n         environment       ``floating-stack''
fdrop       r --        float       ``f-drop''
fnip       r1 r2 -- r2        gforth       ``f-nip''
fdup       r -- r r        float       ``f-dupe''
fover       r1 r2 -- r1 r2 r1        float       ``f-over''
ftuck       r1 r2 -- r2 r1 r2        gforth       ``f-tuck''
fswap       r1 r2 -- r2 r1        float       ``f-swap''
fpick       u -- r        gforth       ``fpick''
 r0 ... ru u -- r0 ... ru r0 .
frot       r1 r2 r3 -- r2 r3 r1        float       ``f-rote''