Missing pdf when using \usetikzlibrary{external} in LyX

Question

I'm trying to use the externalization library in LyX to speed up compilation and generate separate PDF files with each of my tikz figures. But for some reason LyX does not output a separate PDF file that only includes the figure.

Here's the tex file as exported from LyX:

\documentclass[12pt,english]{article}  
\usepackage[T1]{fontenc}  
\usepackage[latin9]{inputenc}  
\usepackage[a4paper]{geometry}
\geometry{verbose,tmargin=3cm,bmargin=3cm,lmargin=2.5cm,rmargin=2.5cm,headheight=1cm,headsep=0.8cm,footskip=1.5cm}
\setcounter{secnumdepth}{0}
\setcounter{tocdepth}{2}
\setlength{\parskip}{\medskipamount}
\setlength{\parindent}{0pt}

\makeatletter
\usepackage{tikz}
\usetikzlibrary{external}
\tikzexternalize[] 
\tikzset{external/system call={pdflatex \tikzexternalcheckshellescape -halt-on-error -interaction=batchmode -jobname "\image" "\texsource" & convert "\image".pdf "\image".eps}}

\makeatother

\usepackage{babel}
\begin{document}
\tikzstyle{place}=[circle,draw=blue,fill=blue!20,line width=2pt]
\begin{tikzpicture}
\node at (0,0) [place] {Ti\textit{k}Z};
\end{tikzpicture}
\end{document}

Under Tools > Preferences > File Handling I changed the converter for LaTeX (pdflatex) -> PDF (pdflatex) to pdflatex -shell-escape $$i

When I compile on my Windows machine I only get the PDF file with the main document, it does not create a separate file with the figure and it does not speed up the compilation at all. What am I missing?

Answer 1

The code posted in the question actually did work. The tricky part in LyX is that LyX converts each picture to a separate PDF that it saves in a temporary directory as scottkosty pointed out to me. The path of this folder can be found under Tools > Preferences > Paths. The files can easily be copied and saved in other directories.

When using pdflatex to compile the conveter LaTeX (pdflatex) -> PDF (pdflatex) needs to be changed under Tools > Preferences > File Handling to pdflatex -shell-escape $$i.

When using XeTeX the converter LaTeX (XeTeX) -> PDF (XeTeX) needs to be changed to xelatex -shell-escape $$i. I also had to pass a subdirectory to tikzexternalize in the preample, e.g. \tikzexternalize[prefix=Figures/].