R + ggplot + pdf device + LaTeX：是否可以一次嵌入字体

Question

我有一个 r-scipt，它通过以下方式生成 PDF...

100 多张图表是用 baseplot 和 ggplot 制作的。这些图表是使用 pdf 设备生成的。我使用 pdf 的原因是我需要嵌入字体（在 tex 标签中使用自定义字体）。
生成图表后，我调用生成 .tex 的 Sweave 以将所有图表收集在一起。
之后我调用 MikTeX 生成 PDF。

事实证明，生成图表所需的 75-95% 的时间都被 embed_fonts 调用占用了。有没有办法减少 embed_fonts （这似乎是 ghostscript 的包装）调用？理想的 vatiant 是只嵌入调用一次。这可能吗？

Answer 1

也许您可以使用应该嵌入字体的 cairo_pdf 设备。
cairo_pdf 似乎比 pdf 慢但比 pdf + embedFonts 快。

当然，只在最终的 pdf 文档中嵌入字体会是更好的解决方案...

library(microbenchmark)

res_pdf <- microbenchmark({
    f = tempfile(fileext = '.pdf')
    pdf(f); pairs(iris); dev.off()
})

res_embed <- microbenchmark({
    f = tempfile(fileext = '.pdf')
    pdf(f); pairs(iris); dev.off()
    embedFonts(f)
})

res_cairo <- microbenchmark({
    f = tempfile(fileext = '.pdf')
    cairo_pdf(f); pairs(iris); dev.off()
})

res_pdf
#> Unit: milliseconds
#>       min      lq     mean   median       uq     max neval
#>  16.67764 17.0388 18.05949 17.32904 18.18776 60.2542   100

res_embed
#> Unit: milliseconds
#>                                                                                               
#>      min       lq     mean   median       uq      max neval
#>  250.046 252.7647 257.4749 255.2785 259.4858 303.0072   100

res_cairo
#> Unit: milliseconds
#>                                                                                   
#>       min       lq     mean   median      uq      max neval
#>  84.25745 86.60512 88.42902 88.36698 89.5705 111.5881   100

Answer 2

另一种解决方案是使用出色的 tikzDevice 包将您的绘图输出为 TikZ。

来自设备设置为 tikz 的 rmarkdown document we can include a knitr 块。

example.Rmd

---
output:
  pdf_document:
    latex_engine: xelatex
header-includes:
  - \renewcommand{\familydefault}{\sfdefault}
  - \usepackage{tikz}
---

```{r setup, include=FALSE}
library(tikzDevice)

# setting the package options so that the font metrics are calculated correctly
options(
  tikzLatexPackages = c(
    getOption("tikzLatexPackages"),
    "\renewcommand{\familydefault}{\sfdefault}"
  )
)
```

# My plot

This text will be set in the default *sans serif* and so will the text found
within the chart below.

```{r, echo=FALSE, dev='tikz'}
pairs(iris)
```

您可以将我的 \renewcommand{\familydefault}{\sfdefault} 替换为设置所选字体所需的任何乳胶命令，例如 \usepackage{charter}。请注意，您必须像我上面的示例一样转义 \。

example.pdf

备选

你可能想提前用另一个脚本生成所有的图，因为你有这么多，而不是在文档生成时内联knitting。我这样做是为了大量运行份报告（1,000 多份），每份报告大约有 20 个图。

# a more simple example due to output size
library(tikzDevice)
mpg <- mtcars$mpg

tikz(file = "example.tex"); hist(mpg); dev.off()

example.tex

% Created by tikzDevice version 0.10.1.2 on 2018-02-21 23:32:57
% !TEX encoding = UTF-8 Unicode
\begin{tikzpicture}[x=1pt,y=1pt]
\definecolor{fillColor}{RGB}{255,255,255}
\path[use as bounding box,fill=fillColor,fill opacity=0.00] (0,0) rectangle (216.81,216.81);
\begin{scope}
\path[clip] (  0.00,  0.00) rectangle (216.81,216.81);
\definecolor{drawColor}{RGB}{0,0,0}

\node[text=drawColor,anchor=base,inner sep=0pt, outer sep=0pt, scale=  1.20] at (120.41,188.07) {\bfseries Histogram of mpg};

\node[text=drawColor,anchor=base,inner sep=0pt, outer sep=0pt, scale=  1.00] at (120.41, 15.60) {mpg};

\node[text=drawColor,rotate= 90.00,anchor=base,inner sep=0pt, outer sep=0pt, scale=  1.00] at ( 10.80,114.41) {Frequency};
\end{scope}
\begin{scope}
\path[clip] (  0.00,  0.00) rectangle (216.81,216.81);
\definecolor{drawColor}{RGB}{0,0,0}

\path[draw=drawColor,line width= 0.4pt,line join=round,line cap=round] ( 54.47, 61.20) -- (186.34, 61.20);

\path[draw=drawColor,line width= 0.4pt,line join=round,line cap=round] ( 54.47, 61.20) -- ( 54.47, 55.20);

\path[draw=drawColor,line width= 0.4pt,line join=round,line cap=round] ( 80.85, 61.20) -- ( 80.85, 55.20);

\path[draw=drawColor,line width= 0.4pt,line join=round,line cap=round] (107.22, 61.20) -- (107.22, 55.20);

\path[draw=drawColor,line width= 0.4pt,line join=round,line cap=round] (133.59, 61.20) -- (133.59, 55.20);

\path[draw=drawColor,line width= 0.4pt,line join=round,line cap=round] (159.96, 61.20) -- (159.96, 55.20);

\path[draw=drawColor,line width= 0.4pt,line join=round,line cap=round] (186.34, 61.20) -- (186.34, 55.20);

\node[text=drawColor,anchor=base,inner sep=0pt, outer sep=0pt, scale=  1.00] at ( 54.47, 39.60) {10};

\node[text=drawColor,anchor=base,inner sep=0pt, outer sep=0pt, scale=  1.00] at ( 80.85, 39.60) {15};

\node[text=drawColor,anchor=base,inner sep=0pt, outer sep=0pt, scale=  1.00] at (107.22, 39.60) {20};

\node[text=drawColor,anchor=base,inner sep=0pt, outer sep=0pt, scale=  1.00] at (133.59, 39.60) {25};

\node[text=drawColor,anchor=base,inner sep=0pt, outer sep=0pt, scale=  1.00] at (159.96, 39.60) {30};

\node[text=drawColor,anchor=base,inner sep=0pt, outer sep=0pt, scale=  1.00] at (186.34, 39.60) {35};

\path[draw=drawColor,line width= 0.4pt,line join=round,line cap=round] ( 49.20, 65.14) -- ( 49.20,163.67);

\path[draw=drawColor,line width= 0.4pt,line join=round,line cap=round] ( 49.20, 65.14) -- ( 43.20, 65.14);

\path[draw=drawColor,line width= 0.4pt,line join=round,line cap=round] ( 49.20, 81.56) -- ( 43.20, 81.56);

\path[draw=drawColor,line width= 0.4pt,line join=round,line cap=round] ( 49.20, 97.98) -- ( 43.20, 97.98);

\path[draw=drawColor,line width= 0.4pt,line join=round,line cap=round] ( 49.20,114.40) -- ( 43.20,114.40);

\path[draw=drawColor,line width= 0.4pt,line join=round,line cap=round] ( 49.20,130.83) -- ( 43.20,130.83);

\path[draw=drawColor,line width= 0.4pt,line join=round,line cap=round] ( 49.20,147.25) -- ( 43.20,147.25);

\path[draw=drawColor,line width= 0.4pt,line join=round,line cap=round] ( 49.20,163.67) -- ( 43.20,163.67);

\node[text=drawColor,rotate= 90.00,anchor=base,inner sep=0pt, outer sep=0pt, scale=  1.00] at ( 34.80, 65.14) {0};

\node[text=drawColor,rotate= 90.00,anchor=base,inner sep=0pt, outer sep=0pt, scale=  1.00] at ( 34.80, 81.56) {2};

\node[text=drawColor,rotate= 90.00,anchor=base,inner sep=0pt, outer sep=0pt, scale=  1.00] at ( 34.80, 97.98) {4};

\node[text=drawColor,rotate= 90.00,anchor=base,inner sep=0pt, outer sep=0pt, scale=  1.00] at ( 34.80,114.40) {6};

\node[text=drawColor,rotate= 90.00,anchor=base,inner sep=0pt, outer sep=0pt, scale=  1.00] at ( 34.80,130.83) {8};

\node[text=drawColor,rotate= 90.00,anchor=base,inner sep=0pt, outer sep=0pt, scale=  1.00] at ( 34.80,147.25) {10};
\end{scope}
\begin{scope}
\path[clip] ( 49.20, 61.20) rectangle (191.61,167.61);
\definecolor{drawColor}{RGB}{0,0,0}

\path[draw=drawColor,line width= 0.4pt,line join=round,line cap=round] ( 54.47, 65.14) rectangle ( 80.85,114.40);

\path[draw=drawColor,line width= 0.4pt,line join=round,line cap=round] ( 80.85, 65.14) rectangle (107.22,163.67);

\path[draw=drawColor,line width= 0.4pt,line join=round,line cap=round] (107.22, 65.14) rectangle (133.59,130.83);

\path[draw=drawColor,line width= 0.4pt,line join=round,line cap=round] (133.59, 65.14) rectangle (159.96, 81.56);

\path[draw=drawColor,line width= 0.4pt,line join=round,line cap=round] (159.96, 65.14) rectangle (186.34, 97.98);
\end{scope}
\end{tikzpicture}

N.B. This is not a complete .tex file and is rather designed to be brought in using \input{example.tex} or otherwise embedded into a complete document. Also, be mindful of the font metric calculations, the saved .tex file may render strangely with different fonts if the metrics are significantly out.

Answer 3

我尝试对第 3 步生成的 PDF 执行 embed_fonts，而不是对第 1 步生成的每个图形调用它，这似乎没问题

R + ggplot + pdf device + LaTeX：是否可以一次嵌入字体

R + ggplot + pdf device + LaTeX: is it possible to embed fonts one time

r

pdf

ggplot2

latex

sweave

example.Rmd

example.pdf

备选

example.tex