pgf title is not centered properly

[asmeurer]

I tested this with the matplotlib master

import numpy as np
import matplotlib.pyplot as plt
plt.figure()
x = np.linspace(0.0, 1.0, 101)
y = x ** 2
plt.plot(x, y)
plt.title('sympy.lambdify\nwith UMFPACK')
plt.savefig('test.pgf')

Then compile this with a test.tex

\documentclass{article}

\usepackage{lmodern}
\usepackage[T1]{fontenc}
\usepackage[utf8x]{inputenc}
\usepackage[scaled=0.8]{DejaVuSansMono}
\bibliographystyle{plain}

% \usepackage[all]{xy}
\usepackage{amsmath}

% for images: png, pdf, etc
\usepackage{graphicx}

% for matplotlib pgf output
\usepackage{pgfplots}

\begin{document}
\begin{figure}[!ht]
\centering
\resizebox{0.9\textwidth}{!}{\input{test.pgf}}
\label{fig:test}
\end{figure}

\end{document}

pdflatex test.tex

The resulting image looks like

If you save as another format, like png, it is centered properly:

I can't reproduce it with all titles, so I'm not sure what exactly is going on with my specific title string.

[jklymak]

It looks like pgf left-justifies the text, which means it's position will likely be incorrect for centered display given the different fonts.

\pgftext[x=2.627738in,y=4.493954in,left,base]{\sffamily\fontsize{12.000000}{14.400000}\selectfont sympy.lambdify}%
\end{pgfscope}%
\begin{pgfscope}%
\pgftext[x=2.682588in,y=4.307333in,left,base]{\sffamily\fontsize{12.000000}{14.400000}\selectfont with UMFPACK}%

[asmeurer]

According to the manual (and my tests), the default behavior for pgf is to center text (if left is left out). But the x value needs to be adjusted to be at the center of the plot.

[jklymak]

Yeah, which happens if the title is one line. But if its two lines the normal text handling seems to get circumvented and the draw_text call only gets a bare string and a position.

[jklymak]

Anyone know the call stack here? Single line titles remain text objects which svg can do a nice job of handling. but if there is a carriage return in the third title the text object isn’t passed to the draw anymore, just the two strings and their positions.

[jklymak]

Right now the text rendering stack doesn't maintain centring for multiple-line text objects. Those objects lose their layout information and default to a more primitive rendering where the text is place based on the default renderer.

I don't see any reason two text objects could be formed at this stage, but its pretty complicated at this stage...

[asmeurer]

If you set the font to be the same as what LaTeX uses, it gets centered correctly

from matplotlib import rcParams
rcParams["font.serif"] = "Computer Modern Roman"
rcParams["font.sans-serif"] = "Computer Modern Sans serif"
rcParams["font.monospace"] = "Computer Modern Typewriter"

[jklymak]

Oh, good. I tried playing around w/ that, but didn't use Computer Modern (duh). Thats the proper solution.

[asmeurer]

Why was this closed?

[anntzer]

I thought the issue was solved (per @jklymak's comment "proper"solution). I can reopen it if you think it's not good enough...