Graphics, Figures & Tables ⇒ tikZ | Using Variables

[ElWray]

I've just started using tikZ and I wonder if there is possibility to use variables in tikzpicture environment. In the pgf manual it's hard to find any information about this.

In my opinion variables create possibility to make more flexible programs.

For example we can declare a "point" variable:

Code: Select all

\coordinate (A) at (1,2);

But I can't change my A. For example I want my A point to be shifted 2cm to the right: A=(3,2). And my A point should have new coordinates after this:

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\coordinate (A) at (A) [xshifted=2cm];

But A is still the same: A=(1,2)

In MetaPost using variables was very easy if we compare it to tikZ.
I hope you know what I mean.

[cgnieder]

It's not entirely clear to me what you want to achieve. Does this help?

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\documentclass{scrartcl}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}

\usepackage{tikz}

\begin{document}

\begin{tikzpicture}
 \draw[help lines] (0,0) grid (3,2) ;
 \coordinate (A) at (1,2);
 \node at (A) {x} ;
 \coordinate (B) at ([xshift=2cm]A);
 \node at (B) {y} ;
\end{tikzpicture}

Even with the same coordinate name:
\begin{tikzpicture}
 \draw[help lines] (0,0) grid (3,2) ;
 \coordinate (A) at (1,2);
 \node at (A) {x} ;
 \coordinate (A) at ([xshift=2cm]A);
 \node at (A) {y} ;
\end{tikzpicture}

\end{document}

Regards

[ElWray]

Yes, this is what I meant. Thanks a lot!

How about numeric variables? Is there a simple way to define them in tikzpicture environment?

For example:

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x=1; %i know it's not correct
y=2;

\coordinate (A) at (x,y); %now it should be A=(1,2)
\coordinate (A) at (x+2,y-1); %now A=(3,1)

[cgnieder]

I'm not at home right now so I can't look myself but in the pgfmanual is a section about calculating coordinates.