The binomial coefficients do not look optimal

The binomial coefficients do not look optimal

[Mikael P. Sundqvist]

[-- Attachment #1.1: Type: text/plain, Size: 779 bytes --]

Hi,

I stumbled upon this (see the attached file for the result):

%%% Test file
\setupbodyfont[10pt]
\starttext
\startTEXpage[offset=10pt]
\type{\tbinom{n}{k}}: $\tbinom{n}{k}$, (does not look good, the vertical
space between $n$ and $k$ is too big) \par
\type{\binom{n}{k}}: $\binom{n}{k}$ (looks fine to me)\par
\type{\dbinom{n}{k}}: $\dbinom{n}{k}$ (does not look good, too big
parenthesis, even for displayed formulas).\par
\stopTEXpage
\stoptext
%%% End of test file

I think something should be changed to get the binomial coefficients to
look better. In particular I am concerned about the rather big parenthesis
in displaystyle (and not so much about the vertical space issue in \tbinom).

/Mikael

PS The result looked better if I used the lucida fonts, if that helps.

[-- Attachment #1.2: Type: text/html, Size: 1026 bytes --]

[-- Attachment #2: ctx-example28.pdf --]
[-- Type: application/pdf, Size: 13743 bytes --]

[-- Attachment #3: Type: text/plain, Size: 492 bytes --]

___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage  : http://www.pragma-ade.nl / http://context.aanhet.net
archive  : https://bitbucket.org/phg/context-mirror/commits/
wiki     : http://contextgarden.net
___________________________________________________________________________________

Re: The binomial coefficients do not look optimal

[Hans Hagen]

[-- Attachment #1: Type: text/plain, Size: 1760 bytes --]

On 9/1/2017 1:56 PM, Mikael P. Sundqvist wrote:
> Hi,
> 
> I stumbled upon this (see the attached file for the result):
> 
> %%% Test file
> \setupbodyfont[10pt]
> \starttext
> \startTEXpage[offset=10pt]
> \type{\tbinom{n}{k}}: $\tbinom{n}{k}$, (does not look good, the vertical 
> space between $n$ and $k$ is too big) \par
> \type{\binom{n}{k}}: $\binom{n}{k}$ (looks fine to me)\par
> \type{\dbinom{n}{k}}: $\dbinom{n}{k}$ (does not look good, too big 
> parenthesis, even for displayed formulas).\par
> \stopTEXpage
> \stoptext
> %%% End of test file
> 
> I think something should be changed to get the binomial coefficients to 
> look better. In particular I am concerned about the rather big 
> parenthesis in displaystyle (and not so much about the vertical space 
> issue in \tbinom).
> 
> /Mikael
> 
> PS The result looked better if I used the lucida fonts, if that helps.
This is indeed font dependent. These binoms use a low level tex 
primitive that uses a threshold for steps and that one is part of the 
math parameters of a font and these are not that good for lm. As I'm 
looking into some other low level side effect I was in the mood for a 
configuration option for \setupmathfractions.

So, in the next beta you can get the effects iof the attached:

- relate the threshold to the bodyfont size
- use normal left/right fences instead

fwiw, cambria and pagella look better too. Upto you to wikify it.

Hans

-----------------------------------------------------------------
                                           Hans Hagen | PRAGMA ADE
               Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
        tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl
-----------------------------------------------------------------

[-- Attachment #2: math-binom.pdf --]
[-- Type: application/pdf, Size: 51047 bytes --]

[-- Attachment #3: Type: text/plain, Size: 492 bytes --]

___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage  : http://www.pragma-ade.nl / http://context.aanhet.net
archive  : https://bitbucket.org/phg/context-mirror/commits/
wiki     : http://contextgarden.net
___________________________________________________________________________________

Re: The binomial coefficients do not look optimal

[Mikael P. Sundqvist]

[-- Attachment #1.1: Type: text/plain, Size: 3003 bytes --]

On Fri, Sep 1, 2017 at 7:49 PM, Hans Hagen <pragma@wxs.nl> wrote:

> On 9/1/2017 1:56 PM, Mikael P. Sundqvist wrote:
>
>> Hi,
>>
>> I stumbled upon this (see the attached file for the result):
>>
>> %%% Test file
>> \setupbodyfont[10pt]
>> \starttext
>> \startTEXpage[offset=10pt]
>> \type{\tbinom{n}{k}}: $\tbinom{n}{k}$, (does not look good, the vertical
>> space between $n$ and $k$ is too big) \par
>> \type{\binom{n}{k}}: $\binom{n}{k}$ (looks fine to me)\par
>> \type{\dbinom{n}{k}}: $\dbinom{n}{k}$ (does not look good, too big
>> parenthesis, even for displayed formulas).\par
>> \stopTEXpage
>> \stoptext
>> %%% End of test file
>>
>> I think something should be changed to get the binomial coefficients to
>> look better. In particular I am concerned about the rather big parenthesis
>> in displaystyle (and not so much about the vertical space issue in \tbinom).
>>
>> /Mikael
>>
>> PS The result looked better if I used the lucida fonts, if that helps.
>>
> This is indeed font dependent. These binoms use a low level tex primitive
> that uses a threshold for steps and that one is part of the math parameters
> of a font and these are not that good for lm. As I'm looking into some
> other low level side effect I was in the mood for a configuration option
> for \setupmathfractions.
>
> So, in the next beta you can get the effects iof the attached:
>
> - relate the threshold to the bodyfont size
> - use normal left/right fences instead
>
> fwiw, cambria and pagella look better too. Upto you to wikify it.
>
> Hans
>
> -----------------------------------------------------------------
>                                           Hans Hagen | PRAGMA ADE
>               Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
>        tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl
> -----------------------------------------------------------------
>
> ____________________________________________________________
> _______________________
> If your question is of interest to others as well, please add an entry to
> the Wiki!
>
> maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/
> listinfo/ntg-context
> webpage  : http://www.pragma-ade.nl / http://context.aanhet.net
> archive  : https://bitbucket.org/phg/context-mirror/commits/
> wiki     : http://contextgarden.net
> ____________________________________________________________
> _______________________
>

Thank you very much, I'm looking forward to the next beta, and I will try
to wikify it when I have tried it out. Also lucida looks better than latin
modern does at the moment.

I am a bit confused about the different versions. I would have guessed that
there was \tbinom and \dbinom and that \binom used one of them depending on
if one is in text mode or in display mode (just as I would expect \frac to
behave like \tfrac in text mode and \dfrac in display mode). But \tbinom
looks very different from \binom in text mode (with more vertical space).
Is this on purpose? Have I missed something?

/Mikael

[-- Attachment #1.2: Type: text/html, Size: 4390 bytes --]

[-- Attachment #2: Type: text/plain, Size: 492 bytes --]

___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage  : http://www.pragma-ade.nl / http://context.aanhet.net
archive  : https://bitbucket.org/phg/context-mirror/commits/
wiki     : http://contextgarden.net
___________________________________________________________________________________