version 1.26, 2003/01/24 22:03:20
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version 1.27, 2003/01/25 13:44:54
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Line 166 AUser CSP
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Line 166 AUser CSP
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\ f.rdp |
\ f.rdp |
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: move-right ( c-addr u1 u2 cfill -- ) |
: push-right ( c-addr u1 u2 cfill -- ) |
\ move string at c-addr u1 right by u2 chars (without exceeding |
\ move string at c-addr u1 right by u2 chars (without exceeding |
\ the original bound); fill the gap with cfill |
\ the original bound); fill the gap with cfill |
>r dup >r rot dup >r ( u1 u2 c-addr R: cfill u2 c-addr ) |
>r over min dup >r rot dup >r ( u1 u2 c-addr R: cfill u2 c-addr ) |
dup 2swap /string cmove> |
dup 2swap /string cmove> |
r> r> r> fill ; |
r> r> r> fill ; |
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: f>buf-rdp { f: rf c-addr ur nd up -- } \ gforth |
: f>buf-rdp-try { f: rf c-addr ur nd up um1 -- um2 } |
\G Convert @i{rf} into a string at @i{c-addr ur}. The conversion |
\ um1 is the mantissa length to try, um2 is the actual mantissa length |
\G rules and the meanings of @i{ur nd up} are the same as for |
c-addr ur um1 /string '0 fill |
\G @code{f.rdp}. |
rf c-addr um1 represent if { nexp fsign } |
rf c-addr ur represent if { nexp fsign } |
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nd nexp + up >= |
nd nexp + up >= |
ur nd - 1- dup { beforep } fsign + nexp 0 max >= and if |
ur nd - 1- dup { beforep } fsign + nexp 0 max >= and if |
\ fixed-point notation |
\ fixed-point notation |
c-addr ur beforep nexp - dup { befored } '0 move-right |
c-addr ur beforep nexp - dup { befored } '0 push-right |
c-addr beforep 1- befored min dup { beforez } 0 max bl fill |
c-addr beforep 1- befored min dup { beforez } 0 max bl fill |
fsign if |
fsign if |
'- c-addr beforez 1- 0 max + c! |
'- c-addr beforez 1- 0 max + c! |
endif |
endif |
c-addr ur beforep /string 1 '. move-right |
c-addr ur beforep /string 1 '. push-right |
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nexp nd + |
else \ exponential notation |
else \ exponential notation |
c-addr ur 1 /string 1 '. move-right |
c-addr ur 1 /string 1 '. push-right |
fsign if |
fsign if |
c-addr ur 1 '- move-right |
c-addr ur 1 '- push-right |
endif |
endif |
nexp 1- s>d tuck dabs <<# #s rot sign 'E hold #> { explen } |
nexp 1- s>d tuck dabs <<# #s rot sign 'E hold #> { explen } |
explen 1+ fsign - ur > if \ exponent too large |
ur explen - 1- fsign + { mantlen } |
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mantlen 0< if \ exponent too large |
drop c-addr ur '* fill |
drop c-addr ur '* fill |
else |
else |
c-addr ur + 0 explen negate /string move |
c-addr ur + 0 explen negate /string move |
endif |
endif |
#>> |
#>> mantlen |
endif |
endif |
else \ inf or nan |
else \ inf or nan |
if \ negative |
if \ negative |
c-addr ur 1 '- move-right |
c-addr ur 1 '- push-right |
endif |
endif |
drop |
drop ur |
\ !! align in some way? |
\ !! align in some way? |
endif ; |
endif |
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1 max ur min ; |
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: f>buf-rdp ( rf c-addr ur nd up -- ) \ gforth |
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\G Convert @i{rf} into a string at @i{c-addr ur}. The conversion |
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\G rules and the meanings of @i{ur nd up} are the same as for |
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\G @code{f.rdp}. |
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\ first, get the mantissa length, then convert for real. The |
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\ mantissa length is wrong in a few cases because of different |
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\ rounding; In most cases this does not matter, because the |
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\ mantissa is shorter than expected and the final digits are 0; |
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\ but in a few cases the mantissa gets longer. Then it is |
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\ conceivable that you will see a result that is rounded too much. |
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\ However, I have not been able to construct an example where this |
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\ leads to an unexpected result. |
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swap 0 max swap 0 max |
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fdup 2over 2over 2 pick f>buf-rdp-try f>buf-rdp-try drop ; |
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: f>str-rdp ( rf ur +nd up -- c-addr ur ) \ gforth |
: 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 Convert @i{rf} into a string at @i{c-addr ur}. The conversion |
Line 232 AUser CSP
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Line 249 AUser CSP
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\G fixed-point notation would have too few significant digits, yet |
\G fixed-point notation would have too few significant digits, yet |
\G exponential notation offers fewer significant digits. We recomment |
\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 @i{ur}>=@i{nd}+2, if you want to have fixed-point notation for some |
\G numbers. Currently, trailing digits are cut off. |
\G numbers. |
f>str-rdp type ; |
f>str-rdp type ; |
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0 [if] |
0 [if] |