Mrthfx

Problem

When changing the values of the markers on a scatter plot using the visualization depends on key and when the data comes from a pgfplotstable the marker printing is broken.

If I have the table data explicitly on the addplot it works (see example 3). Similarly, if I have the data coming from a pgfplotstable and without the visualization handler, it also works (see example 1).

However, if I mix both, it just stops printing the markers (see example 2).

Question

How can I make the visualization depends on=value and data coming from a pgfplotstable work together?

Examples

documentclass[convert]{standalone}

usepackage{pgfplots, pgfplotstable}

begin{document}



pgfdeclareplotmark{a}{pgfuseplotmark{*}}

pgfdeclareplotmark{b}{pgfuseplotmark{triangle*}}

pgfdeclareplotmark{c}{pgfuseplotmark{square*}}



pgfplotstableread{%

x y label

0.1  0.15 a

0.45 0.27 c

0.02 0.17 a

0.06 0.1  a

0.9  0.5  b

0.5  0.3  c

0.85 0.52 b

0.12 0.05 a

0.73 0.45 b

0.53 0.25 c

0.76 0.5  b

0.55 0.32 c

}{tab}



begin{tikzpicture}

begin{axis}[legend pos=south east]

  addplot[%

    scatter,

    only marks,

%    visualization depends on=value thisrow{label}aslabel,

%    scatter/@pre marker code/.append style={/tikz/mark=label},

  ]

  table[x=x,y=y]{tab};

  legend{Class 1,Class 2,Class 3}

end{axis}

end{tikzpicture}

begin{tikzpicture}

begin{axis}[legend pos=south east]

  addplot[%

    scatter,

    only marks,

    visualization depends on=value thisrow{label}aslabel,

    scatter/@pre marker code/.append style={/tikz/mark=label},

  ]

  table[x=x,y=y]{tab};

  legend{Class 1,Class 2,Class 3}

  end{axis}

end{tikzpicture}

begin{tikzpicture}

begin{axis}[legend pos=south east]

  addplot[%

  scatter,

  only marks,

  visualization depends on=value thisrow{label}aslabel,

  scatter/@pre marker code/.append style={/tikz/mark=label},

  ]

  table[x=x,y=y]{

    x y label

    0.1  0.15 a

    0.45 0.27 c

    0.02 0.17 a

    0.06 0.1  a

    0.9  0.5  b

    0.5  0.3  c

    0.85 0.52 b

    0.12 0.05 a

    0.73 0.45 b

    0.53 0.25 c

    0.76 0.5  b

    0.55 0.32 c

  };

  legend{Class 1,Class 2,Class 3}

end{axis}

end{tikzpicture}

end{document}

More Context

I'm trying to create some columns from a table, and then trying to plot it. Hence, my need to use a pgfplotstable as the source of the data.

I can change the size of the marker using @pre marker code/.append code handler. However, the @pre marker code/.append style also gives error (not sure if that is related to this problem though).

So, in some sense, I can see that the @pre marker code is seeing the values created with the visualization depends on definition. But for some particular reason it doesn't sees this one with non-numerical values.

Any ideas or hints why this may be happening?