Re: Pringsheim Notation for continued fractions

No worries!

> The vertical bars look good, but the numerators and denominators are
placed flush left instead of centered, which looks odd in cases like
\cFrac{99999}{1}.

Good point! Maybe this is better (although still hack-y)?

\define[2]\cFrac{%
\vcenter{
  \newdimen\WidthOfFirst
  \newdimen\WidthOfSecond
  \newdimen\TrueWidth
  \WidthOfFirst=\widthofstring{\strut$#1$\,}
  \WidthOfSecond=\widthofstring{\strut\vrule\,$#2$}
  \startluacode
    trueWidth = math.max(tex.dimen.WidthOfFirst, tex.dimen.WidthOfSecond)
    context("\\TrueWidth=" .. trueWidth .. "sp")
  \stopluacode

\hbox{\framed[frame=off,width=\TrueWidth,offset=overlay]{\strut$#1$\,}\vrule}%
  \hrule%

\hbox{\strut\vrule\framed[frame=off,width=\TrueWidth,offset=overlay]{\,$#2$}}}%
}

\starttext
First test:
  \startformula
    \startalign
      \NC  a_0+a_0a_1+a_0 a_1 a_2+a_0 a_1 a_2 a_3 \NC  =
\cfrac{a_0}{1-\cfrac{a_1}{1+a_1-\cfrac{a_2}{1+a_2-\cfrac{a_2}{1+a_2-\cfrac{a_3}{1+a_3-\cdots}}}}}\NR
      \NC   \NC  =
\cFrac{a_0}{1}-\cFrac{a_1}{1+a_1}-\cFrac{a_2}{1+a_2}-\cFrac{a_3}{1+a_3}-\cdots\NR
    \stopalign
  \stopformula

Second test:
  \startformula
    \cFrac{99999}{1} = 99999
  \stopformula
\stoptext

Cheers,
Florent

Le lun. 15 juin 2026 à 12:19, Matthias Weber <[email protected]> a
écrit :

> Thanks, Florent,
>
> The vertical bars look good, but the numerators and denominators are
> placed flush left instead of centered, which looks odd in cases like
> \cFrac{99999}{1}.
>
> Matthias
>
> On Jun 14, 2026, at 1:13 PM, Florent Michel <[email protected]> wrote:
>
> Hi,
>
> This is a bit of a hack (and I'm sure there are better solutions), but
> maybe something like the following?
>
> \define[2]\cFrac{%
> \vcenter{
>   \newdimen\WidthOfFirst
>   \newdimen\WidthOfSecond
>   \newdimen\TrueWidth
>   \WidthOfFirst=\widthofstring{\strut$#1$\,}
>   \WidthOfSecond=\widthofstring{\strut\vrule\,$#2$}
>   \startluacode
>     trueWidth = math.max(tex.dimen.WidthOfFirst, tex.dimen.WidthOfSecond)
>     context("\\TrueWidth=" .. trueWidth .. "sp")
>   \stopluacode
>
> \hbox{\offset[width=\TrueWidth]{\strut$#1$\,}\vrule}\hrule\hbox{\strut\vrule\,$#2$}}%
> }
>
> \starttext
> \startformula
> \startalign
> \NC  a_0+a_0a_1+a_0 a_1 a_2+a_0 a_1 a_2 a_3 \NC  =
> \cfrac{a_0}{1-\cfrac{a_1}{1+a_1-\cfrac{a_2}{1+a_2-\cfrac{a_2}{1+a_2-\cfrac{a_3}{1+a_3-\cdots}}}}}\NR
> %\NC   \NC  =
> \frac{a_0|}{|1}-\frac{a_1|}{|1+a_1}-\frac{a_2|}{|1+a_2}-\frac{a_3|}{|1+a_3}-\cdots\NR
> \NC   \NC  =
> \cFrac{a_0}{1}-\cFrac{a_1}{1+a_1}-\cFrac{a_2}{1+a_2}-\cFrac{a_3}{1+a_3}-\cdots\NR
> \stopalign
>
> \stopformula
> \stoptext
>
> Cheers,
> Florent
>
> Le dim. 14 juin 2026 à 17:26, Matthias Weber <[email protected]>
> a écrit :
>
>> Dear All,
>>
>>
>> I would like to typeset continued fractions as attempted and failed in
>> the second line of the following MWE:
>>
>> \def\cFrac#1#2{%
>> \vcenter{\hbox{\strut$#1$\,\vrule}\hrule\hbox{\strut\vrule\,$#2$}}}
>>
>> \starttext
>> \startformula
>> \startalign
>> \NC  a_0+a_0a_1+a_0 a_1 a_2+a_0 a_1 a_2 a_3 \NC  =
>> \cfrac{a_0}{1-\cfrac{a_1}{1+a_1-\cfrac{a_2}{1+a_2-\cfrac{a_2}{1+a_2-\cfrac{a_3}{1+a_3-\cdots}}}}}\NR
>> %\NC   \NC  =
>> \frac{a_0|}{|1}-\frac{a_1|}{|1+a_1}-\frac{a_2|}{|1+a_2}-\frac{a_3|}{|1+a_3}-\cdots\NR
>> \NC   \NC  =
>> \cFrac{a_0}{1}-\cFrac{a_1}{1+a_1}-\cFrac{a_2}{1+a_2}-\cFrac{a_3}{1+a_3}-\cdots\NR
>> \stopalign
>>
>> \stopformula
>> \stoptext
>>
>>
>> The macro is from
>>
>>
>> https://tex.stackexchange.com/questions/68190/how-do-i-typeset-continued-fractions-in-pringsheims-concise-notation
>>
>> where this question is discussed for LaTeX.
>>
>> Unfortunately, the vertical bars on the top of the fractions do not align
>> with the right end of the fraction bar.
>>
>>
>> Any suggestions?
>>
>> Thanks,
>>
>> Matthias
>>
>>
>>
>>
>>
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>>
>
> ___________________________________________________________________________________
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> the Wiki!
>
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>
> ___________________________________________________________________________________
>
>
>
> ___________________________________________________________________________________
> If your question is of interest to others as well, please add an entry to
> the Wiki!
>
> maillist : [email protected] /
> https://mailman.ntg.nl/mailman3/lists/ntg-context.ntg.nl
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>
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___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : [email protected] / https://mailman.ntg.nl/mailman3/lists/ntg-context.ntg.nl
webpage  : https://www.pragma-ade.nl / https://context.aanhet.net (mirror)
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