Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > comp.lang.forth > #135684
| Date | 2026-09-12 22:47 +1000 |
|---|---|
| Subject | Re: ddfloat library: the behavior of >dd |
| Newsgroups | comp.lang.forth |
| References | (1 earlier) <6aa3648f$1@news.ausics.net> <1180jpe$16qki$1@dont-email.me> <1181v83$17dme$1@dont-email.me> <11829tr$3chqi$1@dont-email.me> <11833g2$1818h$1@dont-email.me> |
| From | dxf <dxforth@gmail.com> |
| Message-ID | <6aa549e4$1@news.ausics.net> (permalink) |
| Organization | Ausics - https://newsgroups.ausics.net |
On 12/09/2026 6:45 pm, marcel hendrix wrote:
> ...
> I *only* used the >DD definition found in http://dxforth.webhop.org/finput.html . It has a rough spot: it does not catch invalid floats like JVN's did. S" -NAN +NAN" >DD gave an infinite loop in my tests. Maybe a "safe" >DDS could be added.-marcel
Testing my DDFLOAT.F on Win32Forth:
S" +NAN -NAN" >DD . 0 ok \ flag=false
DD# +NAN -NAN
^^^^
Error(-2): +NAN bad float
OTOH the following *will* get through:
DD# 1e400 ok
f.s {2} +NAN +NAN ok
The original >DD accepts 1e400 gives the same NAN-NAN result.
The latter result when presented to DDFS. will cause an infinite loop due to
the NORMALIZE word. This problem existed in the original DDFS. How one
fixes it depends on what is available. If your forth includes a word that
tests TOS for a NAN/INF etc. then you're in luck. Let's call that word:
NAN? ( r -- flag )
Fixing DDFS. (or what have you) is simply a matter of testing for NAN/INF
before passing to NORMALIZE (which BTW can't handle 0.0E either). In your
case the fix would be something like this:
FOVER F0= IF F2DROP S" 0e" EXIT ENDIF
F2DUP NAN? >R NAN? R> OR IF F2DROP S" NAN/INF" EXIT ENDIF
HTH
Back to comp.lang.forth | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
ddfloat library: the behavior of >dd marcel hendrix <mhx@iae.nl> - 2026-09-10 19:33 +0200
Re: ddfloat library: the behavior of >dd Krishna Myneni <krishna.myneni@ccreweb.org> - 2026-09-10 13:35 -0500
Re: ddfloat library: the behavior of >dd marcel hendrix <mhx@iae.nl> - 2026-09-10 22:10 +0200
Re: ddfloat library: the behavior of >dd Krishna Myneni <krishna.myneni@ccreweb.org> - 2026-09-10 16:51 -0500
Re: ddfloat library: the behavior of >dd dxf <dxforth@gmail.com> - 2026-09-11 12:16 +1000
Re: ddfloat library: the behavior of >dd marcel hendrix <mhx@iae.nl> - 2026-09-11 12:05 +0200
Re: ddfloat library: the behavior of >dd marcel hendrix <mhx@iae.nl> - 2026-09-12 00:27 +0200
Re: ddfloat library: the behavior of >dd Krishna Myneni <krishna.myneni@ccreweb.org> - 2026-09-11 20:29 -0500
Re: ddfloat library: the behavior of >dd dxf <dxforth@gmail.com> - 2026-09-12 12:02 +1000
Re: ddfloat library: the behavior of >dd Krishna Myneni <krishna.myneni@ccreweb.org> - 2026-09-12 10:24 -0500
Re: ddfloat library: the behavior of >dd marcel hendrix <mhx@iae.nl> - 2026-09-12 10:45 +0200
Re: ddfloat library: the behavior of >dd dxf <dxforth@gmail.com> - 2026-09-12 19:51 +1000
Re: ddfloat library: the behavior of >dd dxf <dxforth@gmail.com> - 2026-09-12 22:47 +1000
Re: ddfloat library: the behavior of >dd dxf <dxforth@gmail.com> - 2026-09-13 03:14 +1000
Re: ddfloat library: the behavior of >dd Krishna Myneni <krishna.myneni@ccreweb.org> - 2026-09-12 13:02 -0500
Re: ddfloat library: the behavior of >dd dxf <dxforth@gmail.com> - 2026-09-13 15:44 +1000
Re: ddfloat library: the behavior of >dd marcel hendrix <mhx@iae.nl> - 2026-09-13 09:00 +0200
Re: ddfloat library: the behavior of >dd dxf <dxforth@gmail.com> - 2026-09-13 20:33 +1000
Re: ddfloat library: the behavior of >dd dxf <dxforth@gmail.com> - 2026-09-14 13:28 +1000
Re: ddfloat library: the behavior of >dd marcel hendrix <mhx@iae.nl> - 2026-09-14 10:09 +0200
Re: ddfloat library: the behavior of >dd dxf <dxforth@gmail.com> - 2026-09-14 20:00 +1000
Re: ddfloat library: the behavior of >dd marcel hendrix <mhx@iae.nl> - 2026-09-14 12:22 +0200
Re: ddfloat library: the behavior of >dd dxf <dxforth@gmail.com> - 2026-09-14 21:59 +1000
Re: ddfloat library: the behavior of >dd marcel hendrix <mhx@iae.nl> - 2026-09-14 14:26 +0200
Re: ddfloat library: the behavior of >dd dxf <dxforth@gmail.com> - 2026-09-15 01:32 +1000
Re: ddfloat library: the behavior of >dd marcel hendrix <mhx@iae.nl> - 2026-09-14 21:08 +0200
Re: ddfloat library: the behavior of >dd Krishna Myneni <krishna.myneni@ccreweb.org> - 2026-09-14 15:25 -0500
Re: ddfloat library: the behavior of >dd dxf <dxforth@gmail.com> - 2026-09-15 13:11 +1000
Re: ddfloat library: the behavior of >dd marcel hendrix <mhx@iae.nl> - 2026-09-15 14:06 +0200
Re: ddfloat library: the behavior of >dd dxf <dxforth@gmail.com> - 2026-09-16 00:05 +1000
Re: ddfloat library: the behavior of >dd anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-09-14 15:00 +0000
Re: ddfloat library: the behavior of >dd marcel hendrix <mhx@iae.nl> - 2026-09-14 21:15 +0200
Re: ddfloat library: the behavior of >dd Krishna Myneni <krishna.myneni@ccreweb.org> - 2026-09-14 15:29 -0500
Re: ddfloat library: the behavior of >dd anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-09-14 20:58 +0000
Re: ddfloat library: the behavior of >dd Krishna Myneni <krishna.myneni@ccreweb.org> - 2026-09-15 07:33 -0500
Re: ddfloat library: the behavior of >dd anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-09-15 15:53 +0000
Re: ddfloat library: the behavior of >dd Krishna Myneni <krishna.myneni@ccreweb.org> - 2026-09-15 15:23 -0500
Re: ddfloat library: the behavior of >dd Krishna Myneni <krishna.myneni@ccreweb.org> - 2026-09-15 17:53 -0500
csiph-web