plot_title kwarg is ignored

[kalmarek]

MWE:

plotgrid = plot(plot(x->x^2, title="f(x) = x²"), plot(x->sin(x), title="f(x) = sin(x)"), 
    layout=grid(1,2), link=:y, plot_title = "Some functions")

EDIT:
oh, sorry, just found out that the attribute is (Note: Not currently implemented).

any workaround how to add a global title to grid of sub-plots?

[BeastyBlacksmith]

That depends on the backend used. Generally one can add an empty subplot that only has a title at the top of the layout.
In the pgfplotsx-backend you can also use an annotation, but finding the right coordinates is a bit of trial and error, might also work for other backends, but not sure.

[BeastyBlacksmith]

I actually started implementing it in #2363 (without the backend implementations though)

[fbanning]

Ahoy, what's the current status of this issue? We would be very interested in using the plot_title kwarg for our plots without having to use a workaround. Thanks for any updates in advance, best wishes.

[bgroenks96]

Could someone post a code example for a workaround, like the empty plot thing?

The example provided here kind of works, but it's a bit ugly since you can still the see the plot in the background of the title...

[TheCedarPrince]

Hey @BeastyBlacksmith and Plots.jl team! Great work here! I was just wondering, what is the status on this issue? As @bgroenks96 pointed out, there was a bit of a hack that I am using as well. Here is an example of me working around this issue that looks something like this (the code is not too pretty!):

using DataFrames
using Plots

df = rand(5, 5) * 10 |> DataFrame

function pairplot(df)
    rows, cols = size(df)
    y = ones(3)
    title = Plots.scatter(
        y,
        marker = 0,
        markeralpha = 0,
        annotations = (2, y[2], Plots.text("Pair plot")),
        axis = ([], false),
        leg = false,
        size = (200, 100),
    )
    plots = []
    for row = 1:rows, col = 1:cols
        if row == rows && col == 1
            push!(
                plots,
                scatter(
                    df[row],
                    df[col],
                    xtickfont = font(4),
                    ytickfont = font(4),
                    legend = false,
                    xlabel = "foo",
                    xguidefontsize = font(4),
                    ylabel = "bar",
                    yguidefontsize = font(4),
                ),
            )

        elseif row == rows
            push!(
                plots,
                scatter(
                    df[row],
                    df[col],
                    xtickfont = font(4),
                    ytickfont = font(4),
                    legend = false,
                    xlabel = "foo",
                    xguidefontsize = font(4),
                ),
            )
        elseif col == 1
            push!(
                plots,
                scatter(
                    df[row],
                    df[col],
                    xtickfont = font(4),
                    ytickfont = font(4),
                    legend = false,
                    ylabel = "bar",
                    yguidefontsize = font(4),
                ),
            )
        else
            push!(
                plots,
                scatter(
                    df[row],
                    df[col],
                    xtickfont = font(4),
                    ytickfont = font(4),
                    legend = false,
                ),
            )
        end
    end
    plot(
        title,
        plot(plots..., layout = (rows, cols)),
        layout = grid(2, 1, heights = [0.05, 0.95]),
    )
end

pairplot(df)

Which produces this image: