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My tikz does not want to label the angle within the figure. Whenever I try to use the command "$\alpha$" inside the pic arguments tikz ignores it. I do not know how to proceed. Any suggestions for the code are welcome. Thank you for the help.

\draw (0,0) -- (0,2) -- (5.46,2) -- (2,0) -- (0,0);
\coordinate [label=below:\(A\)] (A) at (0,0);
\coordinate [label=below:\(B\)] (B) at (2,0);
\coordinate [label=above:\(C\)] (C) at (5.46,2);
\coordinate [label=above:\(D\)] (D) at (0,2);
\coordinate [label=left:\(2\)] (E) at (0,1);
\coordinate [label=below:\(2\)] (F) at (1,0);
\coordinate (G) at (3.5,0);
\draw[dashed] (2,0) -- (3.5,0);
\draw (G) -- (B) -- (C)
pic [draw=black, thick, angle radius=1cm, "$\alpha$"] {angle=G--B--C};

marked as duplicate by Torbjørn T. tikz-pgf Sep 13 '16 at 17:44

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  • 2
    I can see the label when I compile your code. Do you not see the \alpha in the picture? – Alenanno Apr 29 '16 at 15:18
  • @Alenanno No. It accuses 16 errors "as missing \endcsname". I do not know how to fix it. – Mark Fantini Apr 30 '16 at 2:21
  • Does precisely the code you posted give an error when you copy-paste it into a new, empty .tex file and compile? I'm betting not. We need an example we can reproduce the issue with. However, as a guess: in your real document (which does give the error), try adding babel to the list of TikZ libraries you are loading. – cfr Apr 30 '16 at 2:53
  • @cfr It fixed it! What changes does babel introduce? – Mark Fantini Apr 30 '16 at 3:06
  • 1
    I can't tell you exactly because you've not provided the code required to reproduce the problem. I assume you are loading babel with a language and using active short hands, presumably including the ". The TikZ library works around the problems this otherwise causes. – cfr Apr 30 '16 at 3:16

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