Q: about \externalfile from metafun-p.pdf

Q: about \externalfile from metafun-p.pdf

[Alexander Lazic]

Hi,

i'm starting to learn context and therefore i have copied some examples
from metafun-p.pdf and get the following error:

---
! Undefined control sequence.
l.42 \externalfile
                  [mprun.21][width=5cm]
---
---
texexec  --version

 TeXExec 5.4.3 - ConTeXt / PRAGMA ADE 1997-2005

               texexec : TeXExec 5.4.3 - ConTeXt / PRAGMA ADE 1997-2005
               texutil : TeXUtil 9.0.0 - ConTeXt / PRAGMA ADE 1992-2004
                   tex : pdfeTeX, 3.141592-1.30.3-2.2 (Web2C 7.5.5)
               context : ver: 2005.07.27
               cont-en : ver: 2005.07.27  fmt: 2005.10.1  mes: english

        total run time : 2 seconds
---
The context code:

---
\language[de]

\setupcolors[state=start]
\setupoutput[pdftex]
\setuppapersize[A4][A4]

\setuppagenumbering[location={footer,right}]
\setupfootertexts[][{Seite \pagenumber{} von \totalnumberofpages}]

\starttext
% in the metapost_test is the code from page 118 => beginfig(21) ;...
\startMPrun
  input metapost_test;
\stopMPrun

\externalfile[mprun.21][width=5cm]

\showsetups
\showlayout
\stoptext
---

Please can any body help, thx.

al ;-)

Re: Q: about \externalfile from metafun-p.pdf

[Christopher Creutzig]

Alexander Lazic wrote:
> i'm starting to learn context and therefore i have copied some examples
> from metafun-p.pdf and get the following error:
> 
> ---
> ! Undefined control sequence.
> l.42 \externalfile
>                   [mprun.21][width=5cm]

 Probably a typo in metafun-p.pdf; try \externalfigure instead.


Christopher

Re: Q: about \externalfile from metafun-p.pdf

[Alexander Lazic]

On Son 02.10.2005 19:54, Christopher Creutzig wrote:
>
> Probably a typo in metafun-p.pdf; try \externalfigure instead.

Thanx this works ;-)

Oh btw: i have see in the syntax-diagramm sin.

1.) is this the sinus function?
2.) i have try

---
\startreusableMPgraphic{sin}

  sin (1);
\stopreusableMPgraphic{sin}

\reuseMPgraphic{sin}
---

and get:

Isolated expression.

Do you know what's going wrong?

al ;-)

Re: Q: about \externalfile from metafun-p.pdf

[Christopher Creutzig]

Alexander Lazic wrote:
> Oh btw: i have see in the syntax-diagramm sin.
> 
> 1.) is this the sinus function?

 Sure.  (The sine function as used by mathematicians.  If you want the
sine of an angle expressed in degrees, I believe you want sind.)

> 2.) i have try
> 
> ---
> \startreusableMPgraphic{sin}
> 
>   sin (1);
> \stopreusableMPgraphic{sin}

 This {sin} at the end is wrong; it's interpreted as text.

> 
> \reuseMPgraphic{sin}
> ---
> 
> and get:
> 
> Isolated expression.
> 
> Do you know what's going wrong?

 It's the same error as trying to “plot” the MP code

 1;

MetaPost is confused since it has no idea what to do with that number
and tells you so.  Since MP can handle more than just numbers, you get a
slightly more general error message that talks about an “expression”
rather than a “number.”


 What you can do is something like

\starttext

\startusableMPgraphic{sin}
  for x := 0 step 0.6282 until 6.282:
    drawdot(10*x, 10*sin(x)) withpen pencircle scaled 1pt;
  endfor
\stopusableMPgraphic

\useMPgraphic{sin}

\stoptext


Or, you can use the fact that in MetaPost you can build up an expression
within a for loop as follows:


\starttext

\startusableMPgraphic{sin}
  draw (0,0)
  for x := 0 step 0.2 until 6.282: ..(10*x, 10*sin(x)) endfor;
\stopusableMPgraphic

\useMPgraphic{sin}

\stoptext


 I think it really helps with MP programming to understand this type of
loops.


Christopher

Re: Q: about \externalfile from metafun-p.pdf

[Alexander Lazic]

On Son 02.10.2005 22:36, Christopher Creutzig wrote:
>Alexander Lazic wrote:
>
>> 2.) i have try
>> 
>> \startreusableMPgraphic{sin}
>> 
>>   sin (1);
>> \stopreusableMPgraphic{sin}
>
> This {sin} at the end is wrong; it's interpreted as text.

This  have i understand ;-)
I called it sin, sorry for confusion.
 
> What you can do is something like
>
>    drawdot(10*x, 10*sin(x)) withpen pencircle scaled 1pt;

Thanx.
Have i right understand, if i want to draw a sinuscurve i must use a
for-loop?

> I think it really helps with MP programming to understand this type of
>loops.

Well i think i must learn mp before context, if i want to draw some
mathemathics functions ;-)

Thanx again for help.

greetings

al ;-)

Re: Q: about \externalfile from metafun-p.pdf

[Christopher Creutzig]

Alexander Lazic wrote:
>>>\stopreusableMPgraphic{sin}
>>
>>This {sin} at the end is wrong; it's interpreted as text.
> 
> 
> This  have i understand ;-)
> I called it sin, sorry for confusion.

 The name is unimportant – my point is that the \stop... commands don't
get arguments.

> Thanx.
> Have i right understand, if i want to draw a sinuscurve i must use a
> for-loop?

 MetaPost is not really a function plotter.  So, yes, you have to use
some sort of loop, although there may be some predefined macros hiding them.


Christopher

function plotting (was: Re: Q: about \externalfile from metafun-p.pdf)

[Alexander Lazic]

On Mon 03.10.2005 19:26, Christopher Creutzig wrote:
>
> MetaPost is not really a function plotter.  So, yes, you have to use
>some sort of loop, although there may be some predefined macros hiding
>them.

Is there a better way in ConTeXt/tex for this?!

Should i use some external Programms for this?

al ;-)

Re: function plotting

[Christopher Creutzig]

Alexander Lazic wrote:
> On Mon 03.10.2005 19:26, Christopher Creutzig wrote:
> 
>>MetaPost is not really a function plotter.  So, yes, you have to use
>>some sort of loop, although there may be some predefined macros hiding
>>them.
> 
> 
> Is there a better way in ConTeXt/tex for this?!
> 
> Should i use some external Programms for this?

 Not really, that causes all sorts of problems when trying to get the
same font all over the place etc.

 But you might be interested (assuming you can read or at least decipher
French) in the pages at
http://melusine.eu.org/syracuse/metapost/galeries/ – complete code
included.  (Those are the predefined macros I was talking about above.)
 I guess something like
http://melusine.eu.org/syracuse/metapost/galeries/courbes02/07riemann-img.html
should wet your appetite. :-)


Regards,
	Christopher

Re: Re: function plotting

[Alexander Lazic]

On Die 04.10.2005 18:07, Christopher Creutzig wrote:
>
> But you might be interested (assuming you can read or at least
>decipher French) in the pages at
>http://melusine.eu.org/syracuse/metapost/galeries/ ? complete code
>included.  (Those are the predefined macros I was talking about above.)

Thanx for that link looks very nice ;-)

greetings

al ;-)

Re: function plotting (was: Re: Q: about \externalfile from metafun-p.pdf)

[Mojca Miklavec]

Alexander Lazic wrote:
> On Mon 03.10.2005 19:26, Christopher Creutzig wrote:
> >
> > MetaPost is not really a function plotter.  So, yes, you have to use
> >some sort of loop, although there may be some predefined macros hiding
> >them.
>
> Is there a better way in ConTeXt/tex for this?!
>
> Should i use some external Programms for this?
>
> al ;-)

I use gnuplot which makes graphs of superb visual quality and has
extensive support for many different function manipulations and weird
stuff that you want to do with it. I do something like:

set terminal latex
set output "file.tex"
set title '\bf My wonderful function $sin(\omega t)$'
set xlabel '$t\ \rm[s]$'
set ylabel '$A$'
plot sin(x)

and then "\input file" inside of the main LaTeX file. Gnuplot cannot
make output in ConTeXt (yet), but perhaps you can include the
resulting PDFs in your ConTeXt source. (Gnuplot is one of the very few
examples where I still use LaTeX.) You can also output the
(ConTeXt-friendly) metapost (with set terminal), but you lose on
quality.

Mojca

Re: function plotting (was: Re: Q: about \externalfile from metafun-p.pdf)

[Alexander Lazic]

On Die 04.10.2005 19:48, Mojca Miklavec wrote:
>
>I use gnuplot which makes graphs of superb visual quality and has
>extensive support for many different function manipulations and weird
>stuff that you want to do with it. 

I have also think on gnuplot, but wasn't sure that i can use the ps/pdf
into my context doc.

>and then "\input file" inside of the main LaTeX file. Gnuplot cannot
>make output in ConTeXt (yet), but perhaps you can include the resulting
>PDFs in your ConTeXt source. (Gnuplot is one of the very few examples
>where I still use LaTeX.) You can also output the (ConTeXt-friendly)
>metapost (with set terminal), but you lose on quality.

Well i will also try with gnuplot.

How much bad is 'lose quality' in %?

greetings

al ;-)

Re: function plotting

[David Arnold]

Alexander,

There is a lot of plots you can do with Metapost. Ordinary, every day  
stuff. For example:

beginfig(1);

% initialize a and c for f(x)=|x-a| and g(x)=c
numeric a, c;
a=-2;
c=2;

% initialize function label abcissas and postions
numeric flabel, glabel;
flabel:=-5;
glabel:=-5;

% define function f(x)=|x-a|
vardef f(expr x)=
     abs(x-a)
enddef;

% draw line with given point and slope
path F;
F:=(-5,f(-5));
for x=-5 step 1 until 5:
     F:=F--(x,f(x));
endfor;

% initialize scale
numeric u; 10u=4cm;

% the line
F:=F scaled 1u;
draw F withcolor blue;

% clipping path
path cpath;
cpath:=(-5,-5)--(5,-5)--(5,5)--(-5,5)--cycle;
cpath:=cpath scaled 1u;

% clip and save current picture
picture pic;
clip currentpicture to cpath;
pic:=currentpicture;

% erase currentpicture
currentpicture:=nullpicture;

% draw grid
for k=-5u step 1u until 5u:
     draw (-5u,k)--(5u,k) withcolor 0.85white;
     draw (k,-5u)--(k,5u) withcolor 0.85white;
endfor;

% draw axes
drawarrow (-5u,0)--(5u,0);
drawarrow (0,-5u)--(0,5u);

% label axes
label.rt(btex $x$ etex, (5.2u,0));
label.top(btex $y$ etex, (0,5.2.u));
label.bot(btex $5$ etex, (5u,0));
label.lft(btex $5$ etex, (0,5u));

% redraw line
draw pic;

% label the functions f(x)=|x-a| and g(x)=c
pair D, E;
D:=(-5,f(-5)) scaled u;
label.lft(btex $f$ etex,D);
E:=(-5,2) scaled u;
label.lft(btex $g$ etex, E);

% draw the graph of g(x)=c
path G;
G:=(-5,2)--(5,2);
G:=G scaled u;
draw G withcolor blue;

endfig;

end.

And for a good stats package, see:

http://www-math.univ-poitiers.fr/~phan/statsmac.html

And for good circuits diagrams, see:

http://www.cnm.es/~pserra/schema/whatis.html

Don't give up on Metapost too soon. It's an awesome language and the  
file size created are small, a plus when you're document includes  
lots of figures and you want it to download in reasonable time on the  
internet.

Re: Re: function plotting

[Alexander Lazic]

Hi,

On Die 04.10.2005 23:17, David Arnold wrote:
> 
[Very helpfull text snipped]

Wow thanx ;-)

>And for a good stats package, see:
>
>http://www-math.univ-poitiers.fr/~phan/statsmac.html
>
>And for good circuits diagrams, see:
>
>http://www.cnm.es/~pserra/schema/whatis.html

Thanx also.

>Don't give up on Metapost too soon. It's an awesome language and the
>file size created are small, a plus when you're document includes lots
>of figures and you want it to download in reasonable time on the
>internet.

Well i give me the time to learn this language ;-)

al ;-)

Re: function plotting

[Christopher Creutzig]

Mojca Miklavec wrote:

> and then "\input file" inside of the main LaTeX file. Gnuplot cannot
> make output in ConTeXt (yet), but perhaps you can include the

 Since afaik ConTeXt does not have an equivalent of LaTeX's picture
environment, I don't see much point in teaching gnuplot some sort of
ConTeXt output.  I'm no gnuplot expert, but my guess is that tweaking
the metapost prologues and some minor code tweaks would probably be the
easiest way to go.

> examples where I still use LaTeX.) You can also output the
> (ConTeXt-friendly) metapost (with set terminal), but you lose on
> quality.

 In what respect do you lose quality?


Christopher

Re: Re: function plotting

[Hans Hagen]

Christopher Creutzig wrote:

>Mojca Miklavec wrote:
>
>  
>
>>and then "\input file" inside of the main LaTeX file. Gnuplot cannot
>>make output in ConTeXt (yet), but perhaps you can include the
>>    
>>
>
> Since afaik ConTeXt does not have an equivalent of LaTeX's picture
>environment, I don't see much point in teaching gnuplot some sort of
>ConTeXt output.  I'm no gnuplot expert, but my guess is that tweaking
>the metapost prologues and some minor code tweaks would probably be the
>easiest way to go.
>  
>
context has some equivalent, positions, which i nowadays never use

even better is to use layers, so if someone is willing to write the code 
for gnuplot, i can provide the context snippets

Hans

-----------------------------------------------------------------
                                          Hans Hagen | PRAGMA ADE
              Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
     tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com
                                             | www.pragma-pod.nl
-----------------------------------------------------------------

Re: Re: function plotting

[David Arnold]

It's been a while since I used gnuplot, but at one time it was able  
to export as Metapost code. Does it still do that?


On Oct 5, 2005, at 12:18 AM, Hans Hagen wrote:

> Christopher Creutzig wrote:
>
>
>> Mojca Miklavec wrote:
>>
>>
>>
>>> and then "\input file" inside of the main LaTeX file. Gnuplot cannot
>>> make output in ConTeXt (yet), but perhaps you can include the
>>>
>>>
>>
>> Since afaik ConTeXt does not have an equivalent of LaTeX's picture
>> environment, I don't see much point in teaching gnuplot some sort of
>> ConTeXt output.  I'm no gnuplot expert, but my guess is that tweaking
>> the metapost prologues and some minor code tweaks would probably  
>> be the
>> easiest way to go.
>>
>>
> context has some equivalent, positions, which i nowadays never use
>
> even better is to use layers, so if someone is willing to write the  
> code for gnuplot, i can provide the context snippets
>
> Hans
>
> -----------------------------------------------------------------
>                                          Hans Hagen | PRAGMA ADE
>              Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
>     tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com
>                                             | www.pragma-pod.nl
> -----------------------------------------------------------------
>
> _______________________________________________
> ntg-context mailing list
> ntg-context@ntg.nl
> http://www.ntg.nl/mailman/listinfo/ntg-context
>
>

David

Re: function plotting

[Hans Hagen]

Mojca Miklavec wrote:

>I use gnuplot which makes graphs of superb visual quality and has
>extensive support for many different function manipulations and weird
>stuff that you want to do with it. I do something like:
>
>set terminal latex
>set output "file.tex"
>set title '\bf My wonderful function $sin(\omega t)$'
>set xlabel '$t\ \rm[s]$'
>set ylabel '$A$'
>plot sin(x)
>
>and then "\input file" inside of the main LaTeX file. Gnuplot cannot
>make output in ConTeXt (yet), but perhaps you can include the
>resulting PDFs in your ConTeXt source. (Gnuplot is one of the very few
>examples where I still use LaTeX.) You can also output the
>(ConTeXt-friendly) metapost (with set terminal), but you lose on
>quality.
>  
>
gnuplot is great indeed, but the output is rather large; it would be nice if there was a real good output mode (say, comparable to the output produced by metapost: compact, parsable); 

btw, is it really that difficult to use gnuplot output in context? 

Hans 

-----------------------------------------------------------------
                                          Hans Hagen | PRAGMA ADE
              Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
     tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com
                                             | www.pragma-pod.nl
-----------------------------------------------------------------

Re: Re: function plotting

[Alexander Lazic]

On Mit 05.10.2005 09:05, Hans Hagen wrote:
>
>gnuplot is great indeed, but the output is rather large; it would be
>nice if there was a real good output mode (say, comparable to the
>output produced by metapost: compact, parsable);

Ack.

>btw, is it really that difficult to use gnuplot output in context? 

Not really because if you use png or i think some other output
fileformats.

But i think you lose some benefit of metapost, or have i the wrong point
of view?!

Greetings

al ;-)

Re: Re: function plotting

[David Munger]

> gnuplot is great indeed, but the output is rather large; it would be nice if there was a real good output mode (say, comparable to the output produced by metapost: compact, parsable); 
> 
> btw, is it really that difficult to use gnuplot output in context? 
> 
> Hans 

I often use metapost output from gnuplot indeed, then pass it through a
short sed script to do stuff like adding \start/stopuseMPgraphic
commands and cleaning the preamble. I think gnuplot does a great job in
general.

For more complex graphs, I prefer the mp-graph package.

Regards,

David

Re: function plotting

[Mojca Miklavec]

Hans Hagen wrote:
> gnuplot is great indeed, but the output is rather large; it would be nice if there was a real good output mode (say, comparable to the output produced by metapost: compact, parsable);

LaTeX mode IS parsable and I often edit it manually (except the part
which does the smooth plotting of functions with lines; smooth lines
are composed from hundreds of points and that part makes the files
huge). Drawing only the points results in a reasonably small file.

> btw, is it really that difficult to use gnuplot output in context?

No. A file context.trm
(http://cvs.sourceforge.net/viewcvs.py/gnuplot/gnuplot/term/) should
be written by modifiying the postscript/metapost/latex.trm and perhaps
some layer should be added in ConTeXt for \startgnuplot ...
\stopgnuplot.

Metapost can already be used, perhaps only some interaction with
ConTeXt is missing (setting point shapes & colors, fonts, ...
somewhere at the beginning or in a separate style file).

To answer Christophers's and Alexander's question about quality of
metapost output: I guess I mixed it up with pslatex when I was talking
about the output quality. You can't express it in percentage. See
http://pub.mojca.org/tex/gnuplot/trlin.pdf for an example graph with
latex/pslatex/mp as rendering terminal.

The second example could be easily manually tuned a bit afterwards.
Linewidths & typesetting in general is a bit worse (from my point of
view), but there's no such quality loss as if you use PNGs.

Mojca

Re: Re: function plotting

[Christopher Creutzig]

Mojca Miklavec wrote:
> about the output quality. You can't express it in percentage. See
> http://pub.mojca.org/tex/gnuplot/trlin.pdf for an example graph with
> latex/pslatex/mp as rendering terminal.

 People often (incorrectly) claim you can't argue preferences, but I'd
say the MP version wins hands down in this particular example. :-)


Christopher

Re: function plotting

[Peter Münster]

On Tue, 4 Oct 2005, Alexander Lazic wrote:

> On Mon 03.10.2005 19:26, Christopher Creutzig wrote:
> >
> > MetaPost is not really a function plotter.  So, yes, you have to use
> >some sort of loop, although there may be some predefined macros hiding
> >them.
> 
> Is there a better way in ConTeXt/tex for this?!

You could also try PSTricks:

\usemodule[pstric]
\starttext
\startPSTRICKS
\psplot[plotpoints=100]{0}{1}{x 360 mul sin}
\stopPSTRICKS
\stoptext

Cheers, Peter

-- 
http://pmrb.free.fr/contact/

Re: Re: function plotting

[Alexander Lazic]

Hi,

On Die 04.10.2005 21:14, Peter Münster wrote:
>
>You could also try PSTricks:
>
>\usemodule[pstric]
>\starttext
>\startPSTRICKS
>\psplot[plotpoints=100]{0}{1}{x 360 mul sin}
>\stopPSTRICKS
>\stoptext

Thanx i have try an get:

figures         : figure pstest-texapp can not be found

but there is the file: pstest-texapp.tex

You can get the output and some otherfiles from:

http://www.none.at/tex/

Greetings

al ;-)

Re: Re: function plotting

[Peter Münster]

On Tue, 4 Oct 2005, Alexander Lazic wrote:

> >\usemodule[pstric]
> >\starttext
> >\startPSTRICKS
> >\psplot[plotpoints=100]{0}{1}{x 360 mul sin}
> >\stopPSTRICKS
> >\stoptext
> 
> Thanx i have try an get:
> 
> figures         : figure pstest-texapp can not be found
> 
> but there is the file: pstest-texapp.tex

Hello Alexander,
I don't understand your problem, but perhaps you should write the psplot
command inside a \pspicture(0,-1)(1,1) ... \endpspicture.
Cheers, Peter

-- 
http://pmrb.free.fr/contact/

Re: Re: function plotting

[luigi.scarso]

Peter Münster wrote:

>On Tue, 4 Oct 2005, Alexander Lazic wrote:
>
>  
>
>>>\usemodule[pstric]
>>>\starttext
>>>\startPSTRICKS
>>>\psplot[plotpoints=100]{0}{1}{x 360 mul sin}
>>>\stopPSTRICKS
>>>\stoptext
>>>      
>>>
>>Thanx i have try an get:
>>
>>figures         : figure pstest-texapp can not be found
>>
>>but there is the file: pstest-texapp.tex
>>    
>>
>
>Hello Alexander,
>I don't understand your problem, but perhaps you should write the psplot
>command inside a \pspicture(0,-1)(1,1) ... \endpspicture.
>Cheers, Peter
>
>  
>
This works for me (I suppose your code is in pstest-texapp.tex):
$> texexec --output=dvips pstest-texapp.tex
$> dvips -o pstest-texapp.ps pstest-texapp.dvi
$> ps2pdf14 pstest-texapp.ps

luigi

Re: Re: function plotting

[Alexander Lazic]

On Mit 05.10.2005 08:43, luigi.scarso wrote:
>Peter Münster wrote:
>
>>I don't understand your problem, but perhaps you should write the
>>psplot command inside a \pspicture(0,-1)(1,1) ... \endpspicture.
>>
>This works for me (I suppose your code is in pstest-texapp.tex):

Thanx both for your answer, i think i need some more time with
context&&metapost ;-)

@all: I will work thru all your answers and tips, thanx again all for
      our help and points ;-))

Greetings from austria.

al ;-)