How to disable warning prints?

[denniskb]

Some of my matplotplusplus calls generate warnings messages that are printed to stdout. Things such as "warning: empty scatter plot". Since I'd like to print to stdout myself this is rather unfortunate. Is there a way to disable all warning prints or perhaps redirect them to a different stream (i.e. /dev/null)? Many thanks!

[alandefreitas]

This is related to how the pipes are created in gnuplot.h and gnuplot.cpp.

It's not hard to reimplement this logic to redirect the messages differently or even copy and paste these files to create another backend locally that would handle the pipes differently, like throwing an exception instead or something like that. I think this request has never come up because only errors are redirected to stdout and the easiest solution is just to fix the error that is leading to the warning.

[denniskb]

I could skip calling scatter() with empty x and y but then the colors of subsequent plots change. Is there a way to "advance the color palette" without issuing a plot call?

[alandefreitas]

The simplest solution is to define explicit colors instead of relying on automatic colors. You can even reuse the automatic colors if you want:

matplotplusplus/source/matplot/core/axes_type.h

Line 2832 in 280659a

std::vector<std::array<float, 4>> colororder_{

If you want to rely on the automatic colors from the axes_type, you can call

matplotplusplus/source/matplot/core/axes_type.h

Line 495 in 280659a

color_array get_color_and_bump();

On the current axes object and ignore the returned value.

This is what the plot objects do under the hood:

matplotplusplus/source/matplot/axes_objects/line.cpp

Line 229 in 280659a

auto c = parent_->get_color_and_bump();