[Tex/LaTex] Saving tikz figures in external file

includeinputtikz-pgf

I have several tikz figures, some of which are over 400 lines of code. This complicates my working on the main file since I have to scroll past all that code quite often so I was thinking I put it in an external file which I can then simply include in my main document. Now I don't know how to proceed, I see two ways:

Putting every picture in a separate file, compile as PDF, include the PDF figures
Putting every picture in a separate file, include the files, compile the main document

Which is the best way to do this? And how exactly should I go about it? For example in option two, I don't know what code is needed in the sub-files: should I start defining a \documentclass and proceed like it was a standalone document or can I just put the code I'm "cutting" out of the main document?

What should I do then? include? input?

MWE

\documentclass{scrreprt}
\usepackage{tikz}
\usepackage{lipsum}
\tikzset{every picture/.style={line width=0.75pt}} %set default line width to 0.75pt        

\begin{document}
\chapter{Foo}
\lipsum[1]

\begin{figure}[h!]
    \centering
    \begin{tikzpicture}[x=0.75pt,y=0.75pt,yscale=-1,xscale=1]

    %Shape: Rectangle [id:dp6874714272670446] 
    \draw   (600.5,167) -- (608.5,167) -- (608.5,181.5) -- (600.5,181.5) -- cycle ;
    %Shape: Rectangle [id:dp25216565311879857] 
    \draw   (569,127) -- (639,127) -- (639,167) -- (569,167) -- cycle ;
    %Shape: Rectangle [id:dp10652138678304235] 
    \draw   (593.5,181.5) -- (614.5,181.5) -- (614.5,188.5) -- (593.5,188.5) -- cycle ;
    %Shape: Rectangle [id:dp27982392636707765] 
    \draw   (572.5,130.71) -- (635.5,130.71) -- (635.5,163.29) -- (572.5,163.29) -- cycle ;
    %Shape: Rectangle [id:dp29031818189807423] 
    \draw   (572.75,193.2) -- (637.25,193.2) -- (637.25,212.43) -- (572.75,212.43) -- cycle ;
    %Shape: Rectangle [id:dp6960940497473749] 
    \draw   (577.35,196.4) -- (581,196.4) -- (581,198.41) -- (577.35,198.41) -- cycle ;
    %Shape: Rectangle [id:dp012575111125552318] 
    \draw   (583.35,196.4) -- (587,196.4) -- (587,198.41) -- (583.35,198.41) -- cycle ;
    %Shape: Rectangle [id:dp7462575500863122] 
    \draw   (589.35,196.4) -- (593,196.4) -- (593,198.41) -- (589.35,198.41) -- cycle ;
    %Shape: Rectangle [id:dp74377024282381] 
    \draw   (595.35,196.4) -- (599,196.4) -- (599,198.41) -- (595.35,198.41) -- cycle ;
    %Shape: Rectangle [id:dp5681813434227054] 
    \draw   (577.35,200.41) -- (581,200.41) -- (581,202.41) -- (577.35,202.41) -- cycle ;
    %Shape: Rectangle [id:dp45670728197953436] 
    \draw   (583.35,200.41) -- (587,200.41) -- (587,202.41) -- (583.35,202.41) -- cycle ;
    %Shape: Rectangle [id:dp4491046180017293] 
    \draw   (589.35,200.41) -- (593,200.41) -- (593,202.41) -- (589.35,202.41) -- cycle ;
    %Shape: Rectangle [id:dp6731288033777918] 
    \draw   (595.35,200.41) -- (599,200.41) -- (599,202.41) -- (595.35,202.41) -- cycle ;
    %Shape: Rectangle [id:dp7160498396948172] 
    \draw   (601.35,196.4) -- (605,196.4) -- (605,198.41) -- (601.35,198.41) -- cycle ;
    %Shape: Rectangle [id:dp13325729640208062] 
    \draw   (607.35,196.4) -- (611,196.4) -- (611,198.41) -- (607.35,198.41) -- cycle ;
    %Shape: Rectangle [id:dp2394144125721973] 
    \draw   (601.35,200.41) -- (605,200.41) -- (605,202.41) -- (601.35,202.41) -- cycle ;
    %Shape: Rectangle [id:dp19114186601978278] 
    \draw   (607.35,200.41) -- (611,200.41) -- (611,202.41) -- (607.35,202.41) -- cycle ;
    %Shape: Rectangle [id:dp6393250197036928] 
    \draw   (616.35,196.4) -- (620,196.4) -- (620,198.41) -- (616.35,198.41) -- cycle ;
    %Shape: Rectangle [id:dp5875707462557691] 
    \draw   (616.35,200.41) -- (620,200.41) -- (620,202.41) -- (616.35,202.41) -- cycle ;
    %Shape: Rectangle [id:dp2632343129417658] 
    \draw   (622.35,196.4) -- (626,196.4) -- (626,198.41) -- (622.35,198.41) -- cycle ;
    %Shape: Rectangle [id:dp16732048982102876] 
    \draw   (628.35,196.4) -- (632,196.4) -- (632,198.41) -- (628.35,198.41) -- cycle ;
    %Shape: Rectangle [id:dp994069766161821] 
    \draw   (622.35,200.41) -- (626,200.41) -- (626,202.41) -- (622.35,202.41) -- cycle ;
    %Shape: Rectangle [id:dp22742437505582824] 
    \draw   (628.35,200.41) -- (632,200.41) -- (632,202.41) -- (628.35,202.41) -- cycle ;
    %Shape: Rectangle [id:dp7394772484697936] 
    \draw   (577.35,204.42) -- (581,204.42) -- (581,206.42) -- (577.35,206.42) -- cycle ;
    %Shape: Rectangle [id:dp22090387903101294] 
    \draw   (583.35,204.42) -- (587,204.42) -- (587,206.42) -- (583.35,206.42) -- cycle ;
    %Shape: Rectangle [id:dp3094625226147294] 
    \draw   (589.35,204.42) -- (593,204.42) -- (593,206.42) -- (589.35,206.42) -- cycle ;
    %Shape: Rectangle [id:dp2693883419330956] 
    \draw   (595.35,204.42) -- (599,204.42) -- (599,206.42) -- (595.35,206.42) -- cycle ;
    %Shape: Rectangle [id:dp879541864109227] 
    \draw   (577.35,208.42) -- (581,208.42) -- (581,210.43) -- (577.35,210.43) -- cycle ;
    %Shape: Rectangle [id:dp005070405348506002] 
    \draw   (583,208.42) -- (599.35,208.42) -- (599.35,210.43) -- (583,210.43) -- cycle ;
    %Shape: Rectangle [id:dp7109131109721036] 
    \draw   (601.35,204.42) -- (605,204.42) -- (605,206.42) -- (601.35,206.42) -- cycle ;
    %Shape: Rectangle [id:dp34805202583561967] 
    \draw   (607.35,204.42) -- (611,204.42) -- (611,206.42) -- (607.35,206.42) -- cycle ;
    %Shape: Rectangle [id:dp88037563000339] 
    \draw   (601.35,208.42) -- (605,208.42) -- (605,210.43) -- (601.35,210.43) -- cycle ;
    %Shape: Rectangle [id:dp199400132263712] 
    \draw   (607.35,208.42) -- (611,208.42) -- (611,210.43) -- (607.35,210.43) -- cycle ;
    %Shape: Rectangle [id:dp4342588107618768] 
    \draw   (616.35,208.42) -- (620,208.42) -- (620,210.43) -- (616.35,210.43) -- cycle ;
    %Shape: Rectangle [id:dp9519101603214133] 
    \draw   (622.35,204.42) -- (626,204.42) -- (626,206.42) -- (622.35,206.42) -- cycle ;
    %Shape: Rectangle [id:dp4542360869287658] 
    \draw   (622.35,208.42) -- (626,208.42) -- (626,210.43) -- (622.35,210.43) -- cycle ;
    %Shape: Rectangle [id:dp5417437553938629] 
    \draw   (628.35,208.42) -- (632,208.42) -- (632,210.43) -- (628.35,210.43) -- cycle ;

    \end{tikzpicture}
\caption{This is just a part of the total picture.}
\end{figure}
\lipsum[2]
\end{document}

Best Answer

Simple answer, you can do both. However, in a very closer inspection, each has its own advantages and disadvantages.

Method 1

%&pdflatex
% !TeX TXS-program:compile = txs:///pdflatex/[--shell-escape]
\documentclass{scrreprt}
\usepackage{tikz}
\usepackage{lipsum}
\tikzset{every picture/.style={line width=0.75pt}} %set default line width to 0.75pt        
\usetikzlibrary{external}
\tikzexternalize[prefix=tikzexfig/]
\usepackage{standalone}
\begin{document}
\chapter{Foo}
\lipsum[1]
\begin{figure*}[h]
    \centering{
        \input{ex.tex}
        \caption{This is just a part of the total picture.}
        \label{f1}
    }
\end{figure*}
\lipsum[2]
\end{document}

Note: tikzexfig is a folder within your master directory.

Update 1: You must escape the shell to compile the document.

ex.tex

 \begin{tikzpicture}[x=0.75pt,y=0.75pt,yscale=-1,xscale=1]
    %Shape: Rectangle [id:dp6874714272670446] 
    \draw   (600.5,167) -- (608.5,167) -- (608.5,181.5) -- (600.5,181.5) -- cycle ;
    \end{tikzpicture}

Advantages:

Easier in-line compilation due to smart caching of figures in pdf.

Disadvantages:

When using for publications, you most certainly have to use standalone package to compile them separately.
Memory limit would be reached (pdftex/LaTeX).
When editing, you must delete the already generated pdf's manually. (I am not yet aware of a better alternative to automate it, yet). I had a good discussion with @DavidCarlisle on putting a wrapper around it, as similar to psfrag. However, the result was a terrible failure ;-).
First compilation with all the figues will take a hell-a-lot of time. Subsequent compilations are much faster.

Method 2

I am not going to discuss it, as it is the standard standalone package implementation.

\documentclass{standalone}
\usepackage{tikz}
\begin{document}
 \begin{tikzpicture}[x=0.75pt,y=0.75pt,yscale=-1,xscale=1]
    %Shape: Rectangle [id:dp6874714272670446] 
    \draw   (600.5,167) -- (608.5,167) -- (608.5,181.5) -- (600.5,181.5) -- cycle ;
    \end{tikzpicture}
\end{document}

Advantages:

Easier file-like externalisation.
Gives your output in different formats. For more info, visit the package documentation.
We can take the output and compile in shorter time.

Disadvantages:

Different sub-files. Atleast, I am not yet aware to include it as in Method 1.

Disclaimer 1: I remember seeing somewhere that tikzexternal and standalone should not be used together. But I don't remember why and not sure of its impacts.

Disclaimer 2: With pdftex/LaTeX, memory limit is a common problem for both the methods per se.

Related Solutions

[Tex/LaTex] Numerical conditional within tikz keys

I am definitely unfamiliar with both beamer and tikz (do not quite get what the \only are supposed to do) but perhaps this could go in the direction you want:

\documentclass{beamer}
\usepackage{tikz}
\usetikzlibrary{chains}
\newcounter{count}

% helper macro:
\long\def\GobToSemiColon #1;{}

\newcommand\myPicture{
\begin{tikzpicture}
  \begin{scope}[start chain = going below]
  \ifnum\value{count}<1 \expandafter\GobToSemiColon\fi
  \ifnum\value{count}>3 \expandafter\GobToSemiColon\fi
  \node[draw, rectangle, on chain] {display only when counter is between
    1 and 3};

  \ifnum\value{count}>-1 \expandafter\GobToSemiColon\fi
  \node[draw, rectangle, on chain] {display only when counter is
    negative}; 

  \ifnum\value{count}<100 \expandafter\GobToSemiColon\fi
  \ifnum\value{count}>200 \expandafter\GobToSemiColon\fi  
  \node[draw, rectangle, on chain] {display only if counter is between
    100 and 200};

  \ifnum\value{count}<3 \expandafter\GobToSemiColon\fi
  \ifnum\value{count}>20 \expandafter\GobToSemiColon\fi
  \node[draw, circle, on chain] {only when counter is in the range 3 to 20};
  \end{scope}
\end{tikzpicture}
}

\begin{document}
\begin{frame}
\only{\setcounter{count}{-3}\myPicture}
\only{\setcounter{count}{105}\myPicture}
\only{\setcounter{count}{39}\myPicture}
\only{\setcounter{count}{2}\myPicture}
\only{\setcounter{count}{5}\myPicture}
\end{frame}
\end{document}

beamer

[Tex/LaTex] Drawing rectilinear curves in Tikz, aka an Etch-a-Sketch drawing

\draw (20,12) -- ++(2,0) -- ++(0,2) -- ++(-3,0) -- ++(45:3);

Use ++ before each new incremental coordinate to make it relative to the last one and put the pencil there.

Here's a complete example:

\documentclass{article}
\usepackage{tikz}
\begin{document}
\tikz\draw (20,12) -- ++(2,0) -- ++(0,2) -- ++(-3,0) -- ++(30:3) {[rounded corners=10pt]-- ++(5,0) -- ++(0,-6)} -- ++(-7,0) -- cycle;
\end{document}

Of course, combining this with the -| or |- path operators can simplify the code even further; the following two pieces of code produce the same result:

\tikz\draw (20,12) -- ++(2,0) -- ++(0,2) -- ++(3,0) -- ++(0,1) -- ++(1,0) -- ++(0,-3) -- ++(2,0);\par\bigskip

and

\tikz\draw (20,12) -| ++(2,2) -| ++(3,1) -- ++(1,0) |- ++(2,-3);

I don't think that defining commands in this case adds anything; in fact, I think it reduces the functionality of the existing syntax (which is already simple). The example demonstrates that you can use, for example, polar coordinates and modify (up to TikZ limitations) the path attributes midways; even if the current question doesn't require this, it's a good thing to have the possibility to do those kind of modification if they are required.