matplotlib/seaborn violin plot with colormap

Question

I want to create a violin plot, with either matplotlib or searborn, in which the plot is colored according to a colormap.

This is what I get:

This is what I would like to get (I used Photoshop here):

How can I obtain the desired plot?

Answer 1

I thought there would be a better was to do this, but, based on @ImportanceOfBeingErnest's comment, I guess this is actually the way to go:

from matplotlib.path import Path
from matplotlib.patches import PathPatch
from mpl_toolkits.axes_grid1.axes_divider import make_axes_locatable


x = [np.random.normal(loc=i, scale=1, size=(100,)) for i in range(5)]

fig, ax = plt.subplots()
violins = ax.violinplot(x)

ymin, ymax = ax.get_ylim()
xmin, xmax = ax.get_xlim()

# create a numpy image to use as a gradient
Nx,Ny=1,1000
imgArr = np.tile(np.linspace(0,1,Ny), (Nx,1)).T
cmap = 'hsv'

for violin in violins['bodies']:
    path = Path(violin.get_paths()[0].vertices)
    patch = PathPatch(path, facecolor='none', edgecolor='none')
    ax.add_patch(patch)
    img = ax.imshow(imgArr, origin="lower", extent=[xmin,xmax,ymin,ymax], aspect="auto",
                    cmap=cmap,
                    clip_path=patch)

# colorbar
ax_divider = make_axes_locatable(ax)
cax = ax_divider.append_axes("right", size="5%", pad="2%")
norm = matplotlib.colors.Normalize(vmin=ymin, vmax=ymax)
cb = matplotlib.colorbar.ColorbarBase(cax, cmap=matplotlib.cm.get_cmap(cmap),
                                norm=norm,
                                orientation='vertical')