| \ switch into postpone state |
\ switch into postpone state |
| ['] postponer is parser state on ; immediate restrict |
['] postponer is parser state on ; immediate restrict |
| |
|
| |
\ f.rdp |
| |
|
| |
: move-right ( c-addr u1 u2 cfill -- ) |
| |
\ move string at c-addr u1 right by u2 chars (without exceeding |
| |
\ the original bound); fill the gap with cfill |
| |
>r dup >r rot dup >r ( u1 u2 c-addr R: cfill u2 c-addr ) |
| |
dup 2swap /string cmove> |
| |
r> r> r> fill ; |
| |
|
| |
: f>buf-rdp { f: rf c-addr ur nd up -- } \ gforth |
| |
\G Convert @i{rf} into a string at @i{c-addr ur}. The conversion |
| |
\G rules and the meanings of @i{ur nd up} are the same as for |
| |
\G @code{f.rdp}. |
| |
rf c-addr ur represent if { nexp fsign } |
| |
nd nexp + up >= |
| |
ur nd - 1- dup { beforep } fsign + nexp 0 max >= and if |
| |
\ fixed-point notation |
| |
c-addr ur beforep nexp - dup { befored } '0 move-right |
| |
c-addr beforep 1- befored min dup { beforez } 0 max bl fill |
| |
fsign if |
| |
'- c-addr beforez 1- 0 max + c! |
| |
endif |
| |
c-addr ur beforep /string 1 '. move-right |
| |
else \ exponential notation |
| |
c-addr ur 1 /string 1 '. move-right |
| |
fsign if |
| |
c-addr ur 1 '- move-right |
| |
endif |
| |
nexp 1- s>d tuck dabs <<# #s rot sign 'E hold #> { explen } |
| |
explen 1+ fsign - ur > if \ exponent too large |
| |
drop c-addr ur '* fill |
| |
else |
| |
c-addr ur + 0 explen negate /string move |
| |
endif |
| |
#>> |
| |
endif |
| |
else \ inf or nan |
| |
if \ negative |
| |
c-addr ur 1 '- move-right |
| |
endif |
| |
drop |
| |
\ !! align in some way? |
| |
endif ; |
| |
|
| |
: f>str-rdp ( rf ur +nd up -- c-addr ur ) \ gforth |
| |
\G Convert @i{rf} into a string at @i{c-addr ur}. The conversion |
| |
\G rules and the meanings of @i{ur +nd up} are the same as for |
| |
\G @code{f.rdp}. The result in in the pictured numeric output buffer |
| |
\G and will be destroyed by anything destroying that buffer. |
| |
rot holdptr @ 1- 0 rot negate /string ( rf +nd up c-addr ur ) |
| |
over holdbuf u< -&17 and throw |
| |
2tuck 2>r f>buf-rdp 2r> ; |
| |
|
| |
: f.rdp ( rf ur +nd up -- ) \ gforth |
| |
\G Print float @i{rf} formatted. The total width of the output is |
| |
\G @i{nr}, the number of digits after the decimal point is @i{+nd}, |
| |
\G the minimum number of significant digits for fixed-point notation |
| |
\G is @i{up}. @code{Set-precision} has no effect on @code{f.rdp}. |
| |
\G Fixed-point notation is used if the number of siginicant digits |
| |
\G would be larger than @i{up} and if the number of digits before the |
| |
\G decimal point would fit. If fixed-point notation is not used, |
| |
\G exponential notation is used, and if that does not fit, asterisks |
| |
\G are printed. We recommend using @i{ur}>=7 to avoid the risk of |
| |
\G numbers not fitting at all. We recommend @i{ur}>=@i{up}+5 to avoid |
| |
\G cases where @code{f.rdp} switches to exponential notation because |
| |
\G fixed-point notation would have too few significant digits, yet |
| |
\G exponential notation offers fewer significant digits. We recomment |
| |
\G @i{ur}>=@i{nd}+2, if you want to have fixed-point notation for some |
| |
\G numbers. Currently, trailing digits are cut off. |
| |
f>str-rdp type ; |
| |
|
| |
0 [if] |
| |
: testx ( rf ur nd up -- ) |
| |
'| emit f.rdp ; |
| |
|
| |
: test ( -- ) |
| |
-0.123456789123456789e-20 |
| |
40 0 ?do |
| |
cr |
| |
fdup 7 3 1 testx |
| |
fdup 7 3 4 testx |
| |
fdup 7 3 0 testx |
| |
fdup 7 7 1 testx |
| |
fdup 7 5 1 testx |
| |
fdup 7 0 2 testx |
| |
fdup 5 2 1 testx |
| |
fdup 4 2 1 testx |
| |
fdup 18 8 5 testx |
| |
'| emit |
| |
10e f* |
| |
loop ; |
| |
[then] |
