[NTG-context] Pgfplots - passing point coordinates by Lua

15 Feb 2014

      Hello,

I just started experimenting with pgfplots package.

I'd have two questions:

1) When plotting/loading a data file: Is it possible to specify the comment mark, which is '#' and '%" by default? I'd need to treat ';' as a comment mark, too.

2) How to pass coordinates of plot points by Lua?

The following code:

----
\usemodule[tikz]
\usemodule[pgfplots]

\startluacode
   data = {{5, 15}, {20, 20}, {24, -24}}

   plot = function(data)
     local str

     for i, v in ipairs(data) do
       str = (str or "") .. "(" .. v[1] .. "," .. v[2] .. ")"
     end

print("Crds=", str)

     context(str)
   end
\stopluacode

\starttext
   \starttikzpicture
     \startaxis[]
       \addplot[mark=none,color=red] coordinates {(11, 5) (12, 18)};    % THIS PLOT IS OK
       \addplot[mark=none,color=red] coordinates {\ctxlua{plot(data)}}; % THIS PLOT HAS NO POINT (?!)
     \stopaxis
   \stoptikzpicture
\stoptext
----

gives error:

"
...
fonts           > fallback modern rm 12pt is loaded
Crds=   (5,15)(20,20)(24,-24)
Package pgfplots: Error! Sorry, I could not read the plot coordinates near '(5,15)(20,20)(24,-24)'. Please check for format mistakes.
! Package pgfplots Warning: the current plot has no coordinates (or all have been filtered away)...
"

Any idea from someone more familiar with pgfplots would be appreciated.

TIA.

Best regards,

Lukas

-- 
Ing. Lukáš Procházka [mailto:LPr@pontex.cz]
Pontex s. r. o.      [mailto:pontex@pontex.cz] [http://www.pontex.cz]
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147 14 Praha 4

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