# Package pgf Error: No shape named is known in tikz-cd commutative diagramm

There are 3 unexpected errors in my tikz-cd commutative diagram, called:

Package pgf Error: No shape named A is known. I think the culprit is a tikzcd arrow in cell 2-2.

How to solve the problem with these errors?

The figure is quite good, however if we can somehow to make an arrow xi with length like nu, it would be perfect.

A MWE is here:

\documentclass[oneside,english]{amsart}
\usepackage{tikz-cd}
\usepackage{stackengine}[2013-09-11]
\usepackage{graphicx}
\begin{document}

\begin{figure}
\begin{center} %8ex
%       \resizebox{0.25\linewidth}{!}{
\begin{tikzcd}[row sep = 40pt, column sep = 40pt, ampersand replacement=\&]
\& K \& \& \& \\
G \arrow[end anchor={[xshift=-1ex]}]{ur}{\mbox{\scalebox{1.5}{$\varepsilon$}}}   \arrow[end anchor={[xshift=-1ex]},swap]{dr}{\mbox{\scalebox{1.5}{$\delta$}}}\&
\arrow[from=A,start anchor={[xshift=-8ex]},end anchor={[xshift=-5ex]}]{r}{\mbox{\scalebox{1.5}{$\zeta$}}}
\& E_m \arrow{r}{\mbox{\scalebox{1.5}{$\mu$}}}\& E_\leq \arrow{r}{\mbox{\scalebox{1.5}{$\nu$}}} \& \mathcal{A}_\leq\\
\& D
\arrow[swap, xshift=-1.5ex,dashrightarrow,near end]{uu}{\mbox{\scalebox{1.5}{$\alpha_1$}}}
[midway]{\ldots}
[near start]{\mbox{\scalebox{1.5}{$\alpha_q$}}}
\arrow[swap, xshift=1.5ex,dashrightarrow]{uu}
\arrow[uu, phantom, xshift=1.6ex,"=:\mathcal{A}"{name=A,right}, midway]
\& \& \&
\end{tikzcd}
%       }
\end{center}
\end{figure}
\end{document}


A current pdf is following:

• It's zeta, not xi (ξ). Also, you should use \eqqcolon from mathtools rather than =:: the colon is not centred on the math axis. Commented Dec 23, 2016 at 23:06

\documentclass{amsart}
$\tikzcdset{ every label/.style={ /tikz/auto, /tikz/font=\everymath\expandafter{\the\everymath\textstyle}, /tikz/inner sep=+0.5ex}, } % \resizebox{0.25\linewidth}{!}{% \begin{tikzcd}[row sep = 40pt, column sep = 40pt, ampersand replacement=\&] \& K \\ G \arrow[end anchor={[xshift=-1ex]}]{ur}{\varepsilon} \arrow[end anchor={[xshift=-1ex]},swap]{dr}{\delta} \& \&[-40pt] =:\mathcal{A} \arrow{r}{\zeta} \& E_m \arrow{r}{\mu} \& E_\leq \arrow{r}{\nu} \& \mathcal{A}_\leq\\ \& D \arrow[swap, xshift=-1.75ex,dashrightarrow,near end]{uu}{\alpha_1} [midway]{\ldots} [near start]{\alpha_q} \arrow[swap, xshift=1.75ex,dashrightarrow]{uu} \end{tikzcd}% % }$

Note how I override the choice of \scriptstyle for the labels. But it's better to use the default \scripstyle, in my opinion.