Multiple elements not visible in pgfplot

Question

I have a few issues with getting a pgfplot right. I do not have much experience with pgfplots and neither online tutorials nor the pgfplots manuel could help me. The plot I want to create is a bar chart with three different plots. The first plot shall only have a y value for x = 1, the other two only for 2 <= x <= 32. My current tex code (with dummy y values) is the following:

\begin{tikzpicture}
    \begin{axis}[
            xlabel=x,
            ylabel=y,
            symbolic x coords={1,2,4,8,16,32},
            xtick=data,
            enlargelimits=0.05,
            legend pos=north east,
            ybar interval=0.7,
            ymajorgrids=true,
            y grid style=dashed,
        ]
    % A
    \addplot coordinates {
        (1,6)
    };

    % B
    \addplot coordinates {
        (2,5) (4,4) (8,3) (16,2) (32,1)
    };

    % C
    \addplot coordinates {
        (2,5) (4,4) (8,3) (16,2) (32,1)
    };

    \legend{A,B,C}
\end{axis}

\end{tikzpicture}

This code produces a plot that looks like this:

Now, there are a few issues with this plot which I do not know how to fix.

1. No values are visible on the x axis
2. The 'A' plot is not visible
3. The plots for x = 32 are missing completely

Thank you very much for your help in advance!

Answer 1

Most of these are linked to your choice of using ybar interval instead of ybar, which is what you should have used. The purpose of the interval type bar plots is that the coordinates define both the width and the height of the bars. If you have two coordinates (1,5)(3,2), you get one bar, of width 2 and height 5. See the pgfplots manual for more details.

This clearly isn't what you want to do, and hence, the first thing to do is change ybar interval to ybar.

In addition, note that xtick=data only takes the first \addplot into account, and in your case the first plot only has one x-value, and you'll get a tick only at the first group of bars. So remove xtick=data.

\documentclass[border=0.2cm]{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=1.18}
\begin{document}
 \begin{tikzpicture}
    \begin{axis}[
            xlabel=x,
            ylabel=y,
            symbolic x coords={1,2,4,8,16,32},
            ytick distance=1, % <-- added
            enlarge x limits={0.15}, % <-- increased value
            legend pos=north east,
            ybar=0.7, % <-- no interval
            ymajorgrids=true,
            y grid style=dashed,
            ymin=0
        ]
    % A
    \addplot coordinates {
        (1,6)
    };

    % B
    \addplot coordinates {
        (2,5) (4,4) (8,3) (16,2) (32,1)
    };

    % C
    \addplot coordinates {
        (2,5) (4,4) (8,3) (16,2) (32,1)
    };

    \legend{A,B,C}
\end{axis}

\end{tikzpicture}
\end{document}