[Tex/LaTex] TikZ: Node position in draw environment

nodestikz-pgf

I am drawing some diagrams of mechanical systems which have many rotated components. For each of these components I am attaching a coordinate system, which is often rotated with the component. I am drawing the coordinates using the draw command and adding labels (x and y) using the node command. I would like the axis label to be in line with the axis (i.e., the arrow points directly at it) regardless of how the coordinate system is rotated. Currently I have done:

\documentclass{standalone}
    \usepackage{tikz}
\begin{document}
    \begin{tikzpicture}
        \draw[<->,rotate around={22.5:(0,0)}](0,1)node[above]{$y$}--(0,0.2)--(1,0.2)node[right]{$x$};
    \end{tikzpicture}
\end{document}

This code results in the following output:

enter image description here

TikZ seems to be interpreting node[above] to mean above using the standard coordinates, instead of "rotating" what it means for the node to be above the end of the line. I would ideally like to be able to write something like node[angle=22.5] to correctly position the label. Is there a way to do this where I can specify the angle instead of just above, right, etc.?

Best Answer

Have you tried something like node[pos=xx]? 

\documentclass{standalone}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}
    \draw[<->,rotate around={22.5:(0,0)}] 
        (0,1) --(0,0.2) node[pos=-0.2] {$y$}
        -- (1,0.2) node[pos=1.2] {$x$};
\end{tikzpicture}
\end{document}

sample output

The pos key of a node places it that position along the segment. pos=0 is the beginning, and pos=1 is the end. pos=0.5 is the middle, sometimes useful, but not here.

We need to place the nodes a little bit before the beginning of the segment and a little bit after. So we subtract a little bit from 0 and add a little bit to 1.

The disadvantage here is that the separation you get is as a fraction of the segment length. So if you want a fixed distance from the end you may need to find another way.

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