# TikZ change coordinate system so Y points downwards

How can I change the default coordinate system of TikZ, so the Y coordinates go downwards, instead of upwards. This is because in the picture I'm trying to draw it is more natural to reference points this way.

I was trying to use negative values in the declaration, but some drawing commands don't really like it, like the grid, where horizontal lines simply don't get drawn this way:

\begin{tikzpicture}[x=1cm,y=-1cm]
\draw (0, 0) grid (7, 7);
\end{tikzpicture}


Result:

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See this one: tex.stackexchange.com/questions/79161/… and also the linked tex.stackexchange.com/questions/55540/… –  percusse Nov 28 '12 at 22:15
@percusse: there might be other problems with negative values (although grid was the first problem I encountered), and those links only deal with the grids. The yscale=1 however seems to have no bad side effects (at least for the cases I need) –  SztupY Nov 28 '12 at 22:21
Any other command is OK with y=-1cm but the grid :) So it's an unlucky start I would say :) –  percusse Nov 28 '12 at 22:24

You could use yscale=-1:

\documentclass{article}
\usepackage{tikz}

\begin{document}

\begin{tikzpicture}[yscale=-1]
\draw (0, 0) grid (7, 7);
\node at (7,7) {A};
\end{tikzpicture}

\end{document}


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That did the job, thanks! –  SztupY Nov 28 '12 at 22:07