# subfiles inside a subfile using relative paths

Is there a way to use subfiles, in a way that you can compile the middle chapters, let me explain by example.

main.tex (root folder)
--Chapter 1 (Chapter 1 folder)
----Section 1.1 (Chapter 1 folder)

Capter 1 is subfile in main.tex
Section 1.1 is subfile in Chapter 1 docment


What I can do is that I can build and view every section, and the main.tex, but I cannot build Chapter on its own. The code:

%main.tex
\usepackage{subfiles}
\begin{document}
\subfile{chap1/chapter1}
...
\end{document}

%chapter1.tex
\documentclass[../main.tex]{subfiles}
\begin{document}
\chapter{Introduction}
\subfile{chap1/purpose}
...
\end{document}

%purpose.tex
\documentclass[../main.tex]{subfiles}
\begin{document}
\section{Purpose}
\end{document}


The trouble I am in stems from the relative paths I believe, if I change the subfile in the chapters to:

\subfile(../chap1/purpose)


I can build the chapter and view it. But then it won't work from the main.tex files. Any idea how to do it right ?

Edit: If there is a method or command to get the absolute path, I would be able to solve it easily, is there such a thing ?

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