Code lua in a table

Code lua in a table

[Fabrice Couvreur]

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Hello,
I want to display the values of Pascal's triangle in a table.
Unfortunately my knowledge of Lua is not sufficient to run this code.
Thank you.
Fabrice

\starttext

\startluacode
     function Binom(n,k)
       if k > n then
             return 0
       elseif (n == 0 or k == 0) then
             return 1
       else
             return (n*Binom(n-1,k-1))/k
     end
             context(Binom(n,k))
    end

    context.startxtable({"align={middle,lohi},
width=1.2cm,offset=0.8ex,bodyfont=9pt"})
    context.startxrow({"background=color,backgroundcolor=green"})
    for i = 0, 10 do
      for j = 0, i do
          context.startxcell()
            context(Binom(i,j))
          context.stopxcell()
      end
    end
    context.stopxrow()

\stopluacode

\stoptext

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Re: Code lua in a table

[Wolfgang Schuster]

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Fabrice Couvreur schrieb am 18.07.2020 um 20:05:
> Hello,
> I want to display the values of Pascal's triangle in a table.
> Unfortunately my knowledge of Lua is not sufficient to run this code.
> Thank you.
> Fabrice
>
> \starttext
>
> \startluacode
>      function Binom(n,k)
>      if k > n then
>              return 0
>        elseif (n == 0 or k == 0) then
>              return 1
>        else
>  return (n*Binom(n-1,k-1))/k
>      end
>  context(Binom(n,k))
Are you sure you want to use context(...) here?
>     end
>
>     context.startxtable({"align={middle,lohi}, 
> width=1.2cm,offset=0.8ex,bodyfont=9pt"})
> context.startxrow({"background=color,backgroundcolor=green"})
>     for i = 0, 10 do
>       for j = 0, i do
>           context.startxcell()
>           context(Binom(i,j))
>           context.stopxcell()
> end
>     end
>     context.stopxrow()
context.stopxtable()

Wolfgang


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Re: Code lua in a table

[Fabrice Couvreur]

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Hi,
I improved the code to be able to display the grid but I cannot display the
coefficients.
Thank you
Fabrice

\starttext

\startluacode
     function Binom(n,k)
       if k > n then
             return 0
       elseif (n == 0 or k == 0) then
             return 1
       else
             return (n*Binom(n-1,k-1))/k
       end

    end

    context.startxtable({"align={middle,lohi},
width=1.2cm,offset=0.8ex,bodyfont=9pt"})
    for i = 1, 10 do
          context.startxrow({"background=color,backgroundcolor=cyan"})
            for j = 1, i do
                  context.startxcell()
                     \ctxlua{context(Binom(i,j))}
                  context.stopxcell()
             end
          context.stopxrow()
    end
   context.stopxtable()

\stopluacode

\stoptext


Le sam. 18 juil. 2020 à 20:32, Wolfgang Schuster <
wolfgang.schuster.lists@gmail.com> a écrit :

> Fabrice Couvreur schrieb am 18.07.2020 um 20:05:
>
> Hello,
> I want to display the values of Pascal's triangle in a table.
> Unfortunately my knowledge of Lua is not sufficient to run this code.
> Thank you.
> Fabrice
>
> \starttext
>
> \startluacode
>      function Binom(n,k)
>        if k > n then
>              return 0
>        elseif (n == 0 or k == 0) then
>              return 1
>        else
>              return (n*Binom(n-1,k-1))/k
>      end
>              context(Binom(n,k))
>
> Are you sure you want to use context(...) here?
>
>     end
>
>     context.startxtable({"align={middle,lohi},
> width=1.2cm,offset=0.8ex,bodyfont=9pt"})
>     context.startxrow({"background=color,backgroundcolor=green"})
>     for i = 0, 10 do
>       for j = 0, i do
>           context.startxcell()
>             context(Binom(i,j))
>           context.stopxcell()
>       end
>     end
>     context.stopxrow()
>
> context.stopxtable()
>
> Wolfgang
>
>
> ___________________________________________________________________________________
> 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
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> archive  : https://bitbucket.org/phg/context-mirror/commits/
> wiki     : http://contextgarden.net
>
> ___________________________________________________________________________________
>

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___________________________________________________________________________________

Re: Code lua in a table

[Wolfgang Schuster]

Fabrice Couvreur schrieb am 18.07.2020 um 22:09:
> Hi,
> I improved the code to be able to display the grid but I cannot display 
> the coefficients.
> Thank you
> Fabrice
> 
> \starttext
> 
> \startluacode
>       function Binom(n,k)
>         if k > n then
>               return 0
>         elseif (n == 0 or k == 0) then
>               return 1
>         else
>               return (n*Binom(n-1,k-1))/k
>         end
> 
>      end
> 
>      context.startxtable({"align={middle,lohi}, 
> width=1.2cm,offset=0.8ex,bodyfont=9pt"})
>      for i = 1, 10 do
>            context.startxrow({"background=color,backgroundcolor=cyan"})
>              for j = 1, i do
>                    context.startxcell()
>                       \ctxlua{context(Binom(i,j))}

Remove \ctxlua:

context(Binom(i,j))

Wolfgang
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Re: Code lua in a table

[Fabrice Couvreur]

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Hi Wolfgang,

It works but why did you ask this question since I finally use context ?

> Are you sure you want to use context(...) here?
>
How not to display the .0 ?
Fabrice

Le sam. 18 juil. 2020 à 22:22, Wolfgang Schuster <
wolfgang.schuster.lists@gmail.com> a écrit :

> Fabrice Couvreur schrieb am 18.07.2020 um 22:09:
> > Hi,
> > I improved the code to be able to display the grid but I cannot display
> > the coefficients.
> > Thank you
> > Fabrice
> >
> > \starttext
> >
> > \startluacode
> >       function Binom(n,k)
> >         if k > n then
> >               return 0
> >         elseif (n == 0 or k == 0) then
> >               return 1
> >         else
> >               return (n*Binom(n-1,k-1))/k
> >         end
> >
> >      end
> >
> >      context.startxtable({"align={middle,lohi},
> > width=1.2cm,offset=0.8ex,bodyfont=9pt"})
> >      for i = 1, 10 do
> >            context.startxrow({"background=color,backgroundcolor=cyan"})
> >              for j = 1, i do
> >                    context.startxcell()
> >                       \ctxlua{context(Binom(i,j))}
>
> Remove \ctxlua:
>
> context(Binom(i,j))
>
> Wolfgang
>
> ___________________________________________________________________________________
> 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
>
> ___________________________________________________________________________________
>

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Re: Code lua in a table

[Fabrice Couvreur]

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Small correction :

\starttext

\startluacode
     function Binom(n,k)
       if k > n then
             return 0
       elseif (n == 0 or k == 0) then
             return 1
       else
             return (n*Binom(n-1,k-1))/k
       end

    end

    context.startxtable({"align={middle,lohi},
width=1cm,offset=0.8ex,bodyfont=9pt"})
    for i = 0, 9 do
          context.startxrow({"background=color,backgroundcolor=cyan"})
            for j = 0, i do
                  context.startxcell()
                     context(Binom(i,j))
                  context.stopxcell()
             end
          context.stopxrow()
    end
   context.stopxtable()

\stopluacode

\stoptext

Le sam. 18 juil. 2020 à 22:25, Fabrice Couvreur <fabrice1.couvreur@gmail.com>
a écrit :

> Hi Wolfgang,
>
> It works but why did you ask this question since I finally use context ?
>
>> Are you sure you want to use context(...) here?
>>
> How not to display the .0 ?
> Fabrice
>
> Le sam. 18 juil. 2020 à 22:22, Wolfgang Schuster <
> wolfgang.schuster.lists@gmail.com> a écrit :
>
>> Fabrice Couvreur schrieb am 18.07.2020 um 22:09:
>> > Hi,
>> > I improved the code to be able to display the grid but I cannot display
>> > the coefficients.
>> > Thank you
>> > Fabrice
>> >
>> > \starttext
>> >
>> > \startluacode
>> >       function Binom(n,k)
>> >         if k > n then
>> >               return 0
>> >         elseif (n == 0 or k == 0) then
>> >               return 1
>> >         else
>> >               return (n*Binom(n-1,k-1))/k
>> >         end
>> >
>> >      end
>> >
>> >      context.startxtable({"align={middle,lohi},
>> > width=1.2cm,offset=0.8ex,bodyfont=9pt"})
>> >      for i = 1, 10 do
>> >            context.startxrow({"background=color,backgroundcolor=cyan"})
>> >              for j = 1, i do
>> >                    context.startxcell()
>> >                       \ctxlua{context(Binom(i,j))}
>>
>> Remove \ctxlua:
>>
>> context(Binom(i,j))
>>
>> Wolfgang
>>
>> ___________________________________________________________________________________
>> 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
>>
>> ___________________________________________________________________________________
>>
>

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___________________________________________________________________________________

Re: Code lua in a table

[Wolfgang Schuster]

Fabrice Couvreur schrieb am 18.07.2020 um 22:25:
> Hi Wolfgang,
> 
> It works but why did you ask this question since I finally use context ?
> 
>     Are you sure you want to use context(...) here?

In your first version you used the context function in the loop to print 
the output of the Binom but the Binom function used context as well, 
this could result in context(context(...)).

> How not to display the .0 ?

Format the content of the context function to show only integer values, 
e.g. context("%d",Binom(...)).

For more information search for formatter in cld-mkiv.pdf.

Wolfgang
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Re: Code lua in a table

[Otared Kavian]

> On 18 Jul 2020, at 22:25, Fabrice Couvreur <fabrice1.couvreur@gmail.com> wrote:
> 
> Hi Wolfgang,
> 
> It works but why did you ask this question since I finally use context ?
> Are you sure you want to use context(...) here?
> How not to display the .0 ?

Besides what Wolfgang suggested, ou can also use 
	context(math.round(Binom(i,j)))
to have integers instead of real numbers.

Best regards: Otared
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Re: Code lua in a table

[Otared Kavian]

> On 18 Jul 2020, at 23:35, Otared Kavian <otared@gmail.com> wrote:
> 
> 
> 
>> On 18 Jul 2020, at 22:25, Fabrice Couvreur <fabrice1.couvreur@gmail.com> wrote:
>> 
>> Hi Wolfgang,
>> 
>> It works but why did you ask this question since I finally use context ?
>> Are you sure you want to use context(...) here?
>> How not to display the .0 ?

Or even better, you can return an integer in your Binom function:

	return math.round((n*Binom(n-1,k-1))/k)

Best regards: Otared
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Re: Code lua in a table

[Jeong Dal]

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Dear Fabrice,

You may split Binom(n,k) function into two functions as following:

*****
\startluacode
P={}
combi = P

function P.fact (n)
  if n <= 0 then
    return 1
  else
    return n * P.fact(n-1)
  end
end

function P.ncr(n,r)
    return P.fact(n)/(P.fact(r)*P.fact(n-r))
end
combi = {
    fact = fact,
    ncr = ncr,
}
\stopluacode
******

Your table is actually Pascal’d triangle. 
Using the above function, I was able to draw Pascal’s triangles.
Hans helped me to complete it.
I couldn’t wikify it at that time because I don’t know how to.  I’ll do it soon.

Here is the whole code for Pascal’s triangle in two different ways using Lua, Metafun and ConTeXt.
You may enhance the code.

\startbuffer[pt1]
numeric n,r,s,u,dx,dy,tt; u := 1.8cm;
path p, q;
pair A,B,start,now;
A := dir(210)*u;
B := dir(-30)*u;
dy := sind(30)*u;
dx := 2*cosd(30)*u;
for n=0 upto 4:
    start := n*dir(210)*u;
    for r=0 upto n:
        s := n-r;
        tt := lua("mp.print(P.ncr(" & decimal n & "," &  decimal r & " ))");
        now := start+r*right*dx;
        dotlabel.top(textext("$\displaystyle {" & decimal n & "\choose" & decimal r & "} = "& decimal tt & "$"),now);
        draw (now+A) -- now -- (now+B);
    endfor;
endfor;
\stopbuffer
\startbuffer[pt2]
numeric n,r,s,u,dx,dy,tt; u := 1cm;
path p, q;
pair A,B,start,now;
A := dir(210)*u;
B := dir(-30)*u;
dy := sind(30)*u;
dx := 2*cosd(30)*u;
for n=0 upto 8:
    start := n*dir(210)*u;
    for r=0 upto n:
        s := n-r;
        tt := lua("mp.print(P.ncr(" & decimal n & "," &  decimal r & " ))");        
        now := start+r*right*dx;
        label(textext("$" & decimal tt & "$"),now);
    endfor;
endfor;
\stopbuffer
\startluacode
P={}
combi = P

function P.fact (n)
  if n <= 0 then
    return 1
  else
    return n * P.fact(n-1)
  end
end

function P.ncr(n,r)
  return P.fact(n)/(P.fact(r)*P.fact(n-r))
end
combi = {
  fact = fact,
  ncr = ncr,
}
\stopluacode
\starttext

\processMPbuffer[pt1]
\blank[big]
\processMPbuffer[pt2]

\stoptext

I hope that it helps.

Best regards,

Dalyoung


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___________________________________________________________________________________

Re: Code lua in a table

[Hans Hagen]

On 7/20/2020 7:56 AM, Jeong Dal wrote:
> Dear Fabrice,
> 
> You may split Binom(n,k) function into two functions as following:
> 
 > see original mail
 >
> Dalyoung
Best stay in a protected namespace ...

\startluacode

     local function fact (n)
         if n <= 0 then
             return 1
         else
             return n * fact(n-1)
         end
     end

     local function ncr(n,r)
         return fact(n)/(fact(r)*fact(n-r))
     end

     userdata.P = {
         fact = fact,
         ncr  = ncr,
     }

     function MP.pascal_ncr(n, r)
         mp.print(ncr(n,r))
     end

\stopluacode

Watch the last definition. This permits

       % tt := lua("mp.print(userdata.P.ncr(" & decimal n & "," & 
decimal r & " ))");

replaced by

         tt := lua.MP.pascal_ncr(n,r);

which looks nicer.

\startbuffer[pt1]
     numeric n, r, s, u, dx, dy, tt;
     path p, q;
     pair A, B, start, now;
     u := 1.8cm;
     A := dir(210)*u;
     B := dir(-30)*u;
     dy := sind(30)*u;
     dx := 2*cosd(30)*u;
     for n=0 upto 4:
         start := n*dir(210)*u;
         for r=0 upto n:
             s := n-r;
           % tt := lua("mp.print(userdata.P.ncr(" & decimal n & "," & 
decimal r & " ))");
           tt := lua.MP.pascal_ncr(n,r);
             now := start+r*right*dx;
             dotlabel.top(textext("$\displaystyle {" & decimal n & 
"\choose" & decimal r & "} = "& decimal tt & "$"),now);
             draw (now+A) -- now -- (now+B);
         endfor;
     endfor;
\stopbuffer

Now, in context lmtx we can have a different kind of abstraction. We can 
do this:

     function MP.pascal_ncr_x()
         mp.print(ncr(mp.scan.pair()))
     end

and then use:

     tt := runscript("MP.pascal_ncr_x()") (n,r) ;

Of course one can decide to pick to two numerics instead, like

     tt := runscript("MP.pascal_ncr_x()") n r ;

but i leave that as exercise.

           % tt := runscript mp_pascal_ncr (n,r) ;
             tt := pascal_ncr (n,r) ;

However, we still have the rather verbose runscript here, so we go 
further, we register pascal as script:

\startluacode
     metapost.registerscript("pascal_ncr",MP.pascal_ncr_x)
\stopluacode

And then define an alias at the metafun end:

\startMPextensions
     newinternal mp_pascal_ncr ; mp_pascal_ncr := scriptindex "pascal_ncr" ;

     def pascal_ncr =
         runscript mp_pascal_ncr
     enddef ;
\stopMPextensions

The internal permits this:

    tt := runscript mp_pascal_ncr (n,r) ;

while the additional def permits

             tt := pascal_ncr (n,r) ;

Now watch out, because we define pascal_ncr here, something
lua.MP.pascal_ncr(n,r) won't work because the last part gets expanded 
because that is what mp does (i'll probably cook something for that some 
day).

Now, to come back to

    "I couldn’t wikify it at that time because I don’t know
     how to.  I’ll do it soon."

looks like you suddenly have an additional challenge,

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
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___________________________________________________________________________________

Re: Code lua in a table

[Fabrice Couvreur]

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Hi all,
Thank you for your contributions, it allows me to progress.
@Hans and Deal
The code is impressive but does not correspond to the shape of the triangle


that I have to make (by convention).
Fabrice

Le lun. 20 juil. 2020 à 10:36, Hans Hagen <j.hagen@xs4all.nl> a écrit :

> On 7/20/2020 7:56 AM, Jeong Dal wrote:
> > Dear Fabrice,
> >
> > You may split Binom(n,k) function into two functions as following:
> >
>  > see original mail
>  >
> > Dalyoung
> Best stay in a protected namespace ...
>
> \startluacode
>
>      local function fact (n)
>          if n <= 0 then
>              return 1
>          else
>              return n * fact(n-1)
>          end
>      end
>
>      local function ncr(n,r)
>          return fact(n)/(fact(r)*fact(n-r))
>      end
>
>      userdata.P = {
>          fact = fact,
>          ncr  = ncr,
>      }
>
>      function MP.pascal_ncr(n, r)
>          mp.print(ncr(n,r))
>      end
>
> \stopluacode
>
> Watch the last definition. This permits
>
>        % tt := lua("mp.print(userdata.P.ncr(" & decimal n & "," &
> decimal r & " ))");
>
> replaced by
>
>          tt := lua.MP.pascal_ncr(n,r);
>
> which looks nicer.
>
> \startbuffer[pt1]
>      numeric n, r, s, u, dx, dy, tt;
>      path p, q;
>      pair A, B, start, now;
>      u := 1.8cm;
>      A := dir(210)*u;
>      B := dir(-30)*u;
>      dy := sind(30)*u;
>      dx := 2*cosd(30)*u;
>      for n=0 upto 4:
>          start := n*dir(210)*u;
>          for r=0 upto n:
>              s := n-r;
>            % tt := lua("mp.print(userdata.P.ncr(" & decimal n & "," &
> decimal r & " ))");
>            tt := lua.MP.pascal_ncr(n,r);
>              now := start+r*right*dx;
>              dotlabel.top(textext("$\displaystyle {" & decimal n &
> "\choose" & decimal r & "} = "& decimal tt & "$"),now);
>              draw (now+A) -- now -- (now+B);
>          endfor;
>      endfor;
> \stopbuffer
>
> Now, in context lmtx we can have a different kind of abstraction. We can
> do this:
>
>      function MP.pascal_ncr_x()
>          mp.print(ncr(mp.scan.pair()))
>      end
>
> and then use:
>
>      tt := runscript("MP.pascal_ncr_x()") (n,r) ;
>
> Of course one can decide to pick to two numerics instead, like
>
>      tt := runscript("MP.pascal_ncr_x()") n r ;
>
> but i leave that as exercise.
>
>            % tt := runscript mp_pascal_ncr (n,r) ;
>              tt := pascal_ncr (n,r) ;
>
> However, we still have the rather verbose runscript here, so we go
> further, we register pascal as script:
>
> \startluacode
>      metapost.registerscript("pascal_ncr",MP.pascal_ncr_x)
> \stopluacode
>
> And then define an alias at the metafun end:
>
> \startMPextensions
>      newinternal mp_pascal_ncr ; mp_pascal_ncr := scriptindex "pascal_ncr"
> ;
>
>      def pascal_ncr =
>          runscript mp_pascal_ncr
>      enddef ;
> \stopMPextensions
>
> The internal permits this:
>
>     tt := runscript mp_pascal_ncr (n,r) ;
>
> while the additional def permits
>
>              tt := pascal_ncr (n,r) ;
>
> Now watch out, because we define pascal_ncr here, something
> lua.MP.pascal_ncr(n,r) won't work because the last part gets expanded
> because that is what mp does (i'll probably cook something for that some
> day).
>
> Now, to come back to
>
>     "I couldn’t wikify it at that time because I don’t know
>      how to.  I’ll do it soon."
>
> looks like you suddenly have an additional challenge,
>
> 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
>
> ___________________________________________________________________________________
>

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___________________________________________________________________________________
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
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wiki     : http://contextgarden.net
___________________________________________________________________________________

Re: Code lua in a table

[Jeong Dal]

Dear Hans,

Thank you for new methods!
It would take some time for me to understand them fully.

Learning Lua, metafun, lmtx, wiki is always a challenge for me.
I also wonder where is the boundary of ConTeXt.

I hope that you and all members in this list are well from COVID-19.

Thank you again.

Best regards,

Dalyoung

> 2020. 7. 20. 오후 5:36, Hans Hagen <j.hagen@xs4all.nl> 작성:
> 
> On 7/20/2020 7:56 AM, Jeong Dal wrote:
>> Dear Fabrice,
>> You may split Binom(n,k) function into two functions as following:
> > see original mail
> >
>> Dalyoung
> Best stay in a protected namespace ...
> 
> \startluacode
> 
>    local function fact (n)
>        if n <= 0 then
>            return 1
>        else
>            return n * fact(n-1)
>        end
>    end
> 
>    local function ncr(n,r)
>        return fact(n)/(fact(r)*fact(n-r))
>    end
> 
>    userdata.P = {
>        fact = fact,
>        ncr  = ncr,
>    }
> 
>    function MP.pascal_ncr(n, r)
>        mp.print(ncr(n,r))
>    end
> 
> \stopluacode
> 
> Watch the last definition. This permits
> 
>      % tt := lua("mp.print(userdata.P.ncr(" & decimal n & "," & decimal r & " ))");
> 
> replaced by
> 
>        tt := lua.MP.pascal_ncr(n,r);
> 
> which looks nicer.
> 
> \startbuffer[pt1]
>    numeric n, r, s, u, dx, dy, tt;
>    path p, q;
>    pair A, B, start, now;
>    u := 1.8cm;
>    A := dir(210)*u;
>    B := dir(-30)*u;
>    dy := sind(30)*u;
>    dx := 2*cosd(30)*u;
>    for n=0 upto 4:
>        start := n*dir(210)*u;
>        for r=0 upto n:
>            s := n-r;
>          % tt := lua("mp.print(userdata.P.ncr(" & decimal n & "," & decimal r & " ))");
>          tt := lua.MP.pascal_ncr(n,r);
>            now := start+r*right*dx;
>            dotlabel.top(textext("$\displaystyle {" & decimal n & "\choose" & decimal r & "} = "& decimal tt & "$"),now);
>            draw (now+A) -- now -- (now+B);
>        endfor;
>    endfor;
> \stopbuffer
> 
> Now, in context lmtx we can have a different kind of abstraction. We can do this:
> 
>    function MP.pascal_ncr_x()
>        mp.print(ncr(mp.scan.pair()))
>    end
> 
> and then use:
> 
>    tt := runscript("MP.pascal_ncr_x()") (n,r) ;
> 
> Of course one can decide to pick to two numerics instead, like
> 
>    tt := runscript("MP.pascal_ncr_x()") n r ;
> 
> but i leave that as exercise.
> 
>          % tt := runscript mp_pascal_ncr (n,r) ;
>            tt := pascal_ncr (n,r) ;
> 
> However, we still have the rather verbose runscript here, so we go further, we register pascal as script:
> 
> \startluacode
>    metapost.registerscript("pascal_ncr",MP.pascal_ncr_x)
> \stopluacode
> 
> And then define an alias at the metafun end:
> 
> \startMPextensions
>    newinternal mp_pascal_ncr ; mp_pascal_ncr := scriptindex "pascal_ncr" ;
> 
>    def pascal_ncr =
>        runscript mp_pascal_ncr
>    enddef ;
> \stopMPextensions
> 
> The internal permits this:
> 
>   tt := runscript mp_pascal_ncr (n,r) ;
> 
> while the additional def permits
> 
>            tt := pascal_ncr (n,r) ;
> 
> Now watch out, because we define pascal_ncr here, something
> lua.MP.pascal_ncr(n,r) won't work because the last part gets expanded because that is what mp does (i'll probably cook something for that some day).
> 
> Now, to come back to
> 
>   "I couldn’t wikify it at that time because I don’t know
>    how to.  I’ll do it soon."
> 
> looks like you suddenly have an additional challenge,
> 
> 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
___________________________________________________________________________________

Re: Code lua in a table

[Hans Hagen]

On 7/20/2020 2:40 PM, Jeong Dal wrote:

> I also wonder where is the boundary of ConTeXt.
The boundaries are set and shift by users (the mailing list) and 
curiosity (personal).

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
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archive  : https://bitbucket.org/phg/context-mirror/commits/
wiki     : http://contextgarden.net
___________________________________________________________________________________

Re: Code lua in a table

[Fabrice Couvreur]

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Hello,
I am making progress and I almost get what I want to achieve but I still
have two problems :
how to color cells not containing numbers with the same color as the others
?
how to color in salmon, for example, cells 1 2  ?
                                                                     3
Thank you
Fabrice

\usecolors[X11]

\startuseMPgraphic{DiagonalRule}
  rulethickness := \frameddimension{rulethickness};

  drawoptions(
    withpen pencircle scaled rulethickness
    withcolor \MPcolor{\framedparameter{framecolor}});

  pair leftcorner, rightcorner;
  leftcorner  := (rulethickness, \overlayheight-rulethickness);
  rightcorner := (\overlaywidth-rulethickness, rulethickness);

  draw leftcorner -- rightcorner;
\stopuseMPgraphic

\defineoverlay
  [DiagonalRule]
  [\useMPgraphic{DiagonalRule}]

\define[2]\DiagonalLabel{%
  \setuptabulate [after={\blank[\frameddimension{offset}]}]
  \starttabulate [|p|r|]
    \NC    \NC #2 \NC\NR
    \NC #1 \NC    \NC\NR
  \stoptabulate
}


\starttext
\startluacode
   function Binom(n,k)
        if k > n then
             return ""
        elseif (n == 0 or k == 0) then
             return 1
        else
             return math.round((n*Binom(n-1,k-1))/k)
        end
      end
  context.startxtable({"align={middle,lohi},
width=1cm,offset=0.8ex,bodyfont=9pt,framecolor=cyan"})
  context.startxrow()

context.startxcell({"background=DiagonalRule,background=color,backgroundcolor=thistle2"})
  context("\\DiagonalLabel{\\m{n}}{\\m{k}}")
  context.stopxcell()
  for j = 0, 7 do
  context.startxcell({"background=color,backgroundcolor=thistle2"})
  context(j)
  context.stopxcell()
  end
  context.startxcell({"background=color,backgroundcolor=thistle2"})
  context("\\dots")
  context.stopxcell()
  context.stopxrow()
  for i = 0, 7 do
  context.startxrow()
  context.startxcell({"background=color,backgroundcolor=thistle2"})
  context(i)
  context.stopxcell()
  for j = 0, 8 do
  context.startxcell()
  context(Binom(i,j))
  context.stopxcell()
  end
  context.stopxrow()
  end
  context.startxrow()
  context.startxcell({"background=color,backgroundcolor=thistle2"})
  context("\\dots")
  context.stopxcell()
  for i = 0, 8 do
  context.startxcell({"background=color,backgroundcolor=thistle2"})
  context("")
  context.stopxcell()
  end
  context.stopxrow()
  context.stopxtable()
\stopluacode
\stoptext

Le lun. 20 juil. 2020 à 14:55, Hans Hagen <j.hagen@xs4all.nl> a écrit :

> On 7/20/2020 2:40 PM, Jeong Dal wrote:
>
> > I also wonder where is the boundary of ConTeXt.
> The boundaries are set and shift by users (the mailing list) and
> curiosity (personal).
>
> 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
>
> ___________________________________________________________________________________
>

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___________________________________________________________________________________
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
___________________________________________________________________________________