Plot hist2d with weights

问题

I need to plot a hist2d with contour curves and colorbar from a pandas dataframe.

The dataframe has three cols:

x_col, y_col, z_col

I want to plot something like this where z_col are the weights of the hist2d:

But I don't know how to transform the z_col into a weight 1D array from the hist2d function.

fdf = df.groupby([valueX, valueY], as_index=False).mean().sort([valueX, valueY])
x = fdf[valueX]
y = fdf[valueY]
z = fdf[valueZ]

(... axes instantiation)

bins = 100

counts, xbins, ybins, image = axes.hist2d(x, y, bins=bins, normed=True, weights=z)
axes.contour(counts, extent=[xbins.min(), xbins.max(), ybins.min(), ybins.max()], linewidths=3)

pc = axes.pcolor(counts, cmap=cm.jet)
fig.colorbar(pc)

axes_x.hist(x, bins=bins)
axes_y.hist(y, bins=bins, orientation='horizontal')

来源：https://stackoverflow.com/questions/28150228/plot-hist2d-with-weights