How can I reverse a cycle list in pgfplots?

Question

Is it possible to reverse the order of a cycle list in pgfplots, and if so, how can I do it?

I am using the pgfplots library colorbrewer to color a graph with four plots on it. I selected the palette OrRd because it is has a four-color palette that the colorbrewer website indicates is colorblind and photocopy safe. The palette includes a very light color that is hard to see against the white background of the plot. I would like to use the four darkest colors from the five or six color OrRd palettes, but if I set one of those palettes as the active cycle list, they use the lighter colors first. I would like to issue a command to reverse the order of the cycle list so that the first plot uses the darkest colors and then later plots use lighter colors.

Here is a minimal working example (adapted from Stefan Pinnow's answer below):

\documentclass[border=5pt]{standalone}
\usepackage{pgfplots}
    \usepgfplotslibrary{colorbrewer}
    \pgfplotsset{
    compat=1.16, cycle list/OrRd-6,}
\begin{document}
\begin{tikzpicture}
    \begin{axis}[
        samples=2,
    ]
        \foreach \i in {1,...,4} {
            \addplot+ [very thick] {\i};
        }
    \end{axis}
\end{tikzpicture}
\end{document}

Here is the output of the above code: pgfplots follows the cycle list order and plots lines with lighter colors first and then darker colors. In this case, the lightest four colors of OrRd-6 are used.

Following is the output I desire: pgfplots follows the cycle list in reverse order. It plots using the darkest colors first, and then uses lighter colors.

Answer 1

Thanks to the newly introduced commands in PGFPlots v1.14 reversing the colors of a colormap is quite easy. The only thing remaining is then mapping the colors of the reversed colormap to a cycle list.

For details please have a look at the comments in the code.

% used PGFPlots v1.16
\documentclass[border=5pt]{standalone}
\usepackage{pgfplots}
    \usepgfplotslibrary{colorbrewer}
    \pgfplotsset{
        % load the `cycle list' or `colormap' that contains the colors you want to use
        cycle list/OrRd-6,
        % define own `cycle list' by first creating a custom `colormap' where
        % the colors are reversed ...
        colormap={OrRd-6-reversed}{
            indices of colormap=(
                \pgfplotscolormaplastindexof{OrRd-6},...,0 of OrRd-6
            )
        },
        % ... which then is mapped to a `cycle list'
        cycle list/.define={OrRd-6-reversed}{[of colormap=OrRd-6-reversed]},
    }
\begin{document}
\begin{tikzpicture}
    \begin{axis}[
        % use the custom `cycle list'
        cycle list name=OrRd-6-reversed,
        samples=2,
    ]
        \foreach \i in {1,...,4} {
            \addplot+ [very thick] {\i};
        }
    \end{axis}
\end{tikzpicture}
\end{document}

Answer 2

Stefan Pinnow's solution achieves the desired result, and it provides a way to truly reverse a cycle list, so it answers the question. However, I prefer to minimize the number of commands used to achieve a desired result, so I am posting my solution, which some users may prefer because it only requires a single additional command.

I can get the desired output by setting the cycle list shift key to -(length of cycle list - 1). This approach is simple to implement, but the value of cycle list shift must be customized for each cycle list.

\documentclass[border=5pt]{standalone}
\usepackage{pgfplots}
    \usepgfplotslibrary{colorbrewer}
        \pgfplotsset{
    compat=1.16, cycle list/OrRd-6,}
\begin{document}
\begin{tikzpicture}
    \begin{axis}[
        samples=2,
        cycle list shift=-5
    ]
        \foreach \i in {1,...,4} {
            \addplot+ [very thick] {\i};
        }
    \end{axis}
\end{tikzpicture}
\end{document}