How to save Pictures silently

[Darkhell101]

I want to save pictures silently, but every time the plot will pop out. Please help me.

[alandefreitas]

If the figure is in quiet mode, I believe the save function shouldn't open anything: https://alandefreitas.github.io/matplotplusplus/coding-styles/reactive-vs-quiet-figures/

In the gnuplot backend object, the save function should usually change the gnuplot terminal type temporarily and call draw. This is an implementation detail:

matplotplusplus/source/matplot/backend/gnuplot.cpp

Line 148 in 3fd7593

bool gnuplot::output(const std::string &filename,

You can try to emulate this behavior from outside, but you shouldn't have to. In any case, this might help describe the logic behind the save function.

[Darkhell101]

Thanks. Very helpful.
There is another problem. Chinese words are shown well in the pop window, but shown errorly when saved as png.

[alandefreitas]

The logic for generating the images depends on the gnuplot terminal for that file format. You could try other file formats? One of the formats is .eps, which people use a lot in academic publications. In this case, you can take the eps file and edit its internal content directly. There's also a latex output format. It creates a .tex file and the corresponding .eps file, making the output match the style of the latex template.

[Darkhell101]

I find a funny thing. When saved in pdf format, the SAVE function may do twice and generate two pages in one pdf document.

// Quiet mode
auto f = figure(true);
auto ax = f->gca();
auto p = ax->plot(x,y); // does not draw
p->color("red").line_width(2); // does not draw
f->show(); // draw only once and pause console

when I try the code, compiler reminds me no PLOT method existed.
error: ‘using element_type = class matplot::figure_type’ {aka ‘class matplot::figure_type’} has no member named ‘plot’