Re: Display Engineering Notation with SI Prefix

On 29/08/2024 1:32 am, dxf wrote:

\ Display Engineering Notation with SI Prefix
\
\ Note: If DX-Forth, VFX Forth or Win32Forth with
\ replacement f/p package is available then the code
\ block defining (FE.) may be disabled.
\
\ Inspired by iForth's (F.N) functions
\
\ This code is Public Domain
 
https://pastebin.com/jd676RC7

The (FE.) simulation didn't work for PREC < 3 .  Here's a fix:

: (FE.) ( r n -- adr len )  \ *** only handles n = -1 ***
  drop  fb 3 [char] 0 fill  fb precision represent  <#  if
    >r  1- s>d 3 fm/mod 3 *  dup  abs 0 #s  rot sign
    [char] E hold  rot  fb precision  3 max  rot 1+ /str
    [char] 0 trim  tuck  holds  if  [char] . hold  then
    holds  r> sign
  else  fb precision -trailing  holds  then  #> ;

The following now works ...

1.234e 1e2 f* 2 1 (eng.) type 120  ok

The real (FE.) has no such issues and works as expected ...

VFX Forth 64 for Windows x64
  © MicroProcessor Engineering Ltd, 1998-2023

 Version: 5.43 [build 4241]
 Build date: 22 December 2023

2 set-precision  ok
1.234e 1e2 f* -1 (fe.) type 120.E0 ok