Add legend to plot with only 1 curve

[SandervandenOord]

Currently it is not possible to add a legend to a plot with only 1 curve.
It would be nice if you could do that.

At the moment there's only a workaround such as creating an overlay with the same curve:

curve1 = hv.Curve([3, 4, 5], name='just one line')
curve1 * curve1

Would be nice if adding a legend to a plot would be more intuitive.

See also:
https://stackoverflow.com/questions/55490184/legend-does-not-appear-in-holoviews-for-only-1-line
https://discourse.holoviz.org/t/how-to-get-a-legend-for-just-one-line-curve/121

Version using:
Holoviews 1.13

[LinuxIsCool]

I think that this functionality would be extremely useful when composing plots. I'm struggling to get a legend for an overlay that is a composition of many single curve plots.

[jbednar]

@LinuxIsCool , can you post the code you are trying to run? Normally a legend is generated when you overlay multiple separate curves.

[szarma]

It does in fact show legend when overlaying separate curves, but seems by "over-plotting" the legend entry. Easy to spot with transparency

curves = []
for j in range(10):
    X = np.random.rand(10)
    t = np.arange(len(X))+j*len(X)*1.2
    curves += [hv.Curve((t,X), label='a').opts(alpha = .5)]
hv.Overlay(curves).opts(width=900)

related: https://discourse.holoviz.org/t/minor-aesthetic-inconsistent-behavior-for-legend-entry-referring-to-multiple-curves/4557