pgfplots: How to hide “nodes near coords” if value is 0 (empty)?

Question

Assumed we have this Minimum Working Example (MWE):

\documentclass{standalone}
\usepackage{pgfplots}

\begin{document}
    \begin{tikzpicture}

        \begin{axis}[
            ybar,
            xtick                   = data,
            ymin                    = 0,
            symbolic x coords       = {Bar 1, Bar 2, Bar 3},
            nodes near coords,
            ]

            \addplot coordinates {(Bar 1, 50) (Bar 2, 0) (Bar 3, 50)};%
        \end{axis}

    \end{tikzpicture}
\end{document}

---

Screenshot of the result:

---

Description of the issue:

As you can see, there is some ugly "0" at the middle ybar. How can I avoid/hide nodes near coords if their corresponding value is 0, so the displayed number should be invisible?

Answer 1

A little roundabout perhaps, but this seems to work:

\documentclass{standalone}
\usepackage{pgfplots}

\begin{document}
    \begin{tikzpicture}

        \begin{axis}[
            ybar,
            xtick                   = data,
            ymin                    = 0,
            symbolic x coords       = {Bar 1, Bar 2, Bar 3},
            visualization depends on={y\as\YY},
            nodes near coords={\pgfmathtruncatemacro{\YY}{ifthenelse(\YY==0,0,1)}\ifnum\YY=0\else\pgfmathprintnumber\pgfplotspointmeta\fi},
            ]

            \addplot coordinates {(Bar 1, 50) (Bar 2, 0) (Bar 3, 50)};%
        \end{axis}

    \end{tikzpicture}
\end{document}

Answer 2

I was working on something similar but I struggled (--> does not work) with the logic test.

\documentclass{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=1.12}
\usepackage{xifthen}

% Instiration
% https://tex.stackexchange.com/questions/36114
% https://tex.stackexchange.com/questions/275187

\begin{document}
    \begin{tikzpicture}
    \begin{axis}[
        ybar,
        xtick = data,
        ymin = 0,
        symbolic x coords = {Bar 1, Bar 2, Bar 3},
        visualization depends on={rawy \as \myRawy},
        nodes near coords = {
        \ifthenelse{<Logic Test>} % something like '\myRawy < 0.001'
            {<True Case>} % Do nothing
            {<False Case>} % Print \myRawy
        },
        ]
        \addplot coordinates {(Bar 1, 50) (Bar 2, 0) (Bar 3, 50)};
    \end{axis}
\end{tikzpicture}
\end{document}

Maybe someone here can solve it elegantly.