具有相同颜色的散点图和等高线图

Question

Is it possible to force plt.scatter into the same color levels as plt.contourf and plt.contour ? For example, I have code that makes a plot like this:

to make the first subplot, I use

cs=m[0].scatter(xs,ys,c=obsData,cmap=plt.cm.jet)
m.colorbar(cs)

To make the second subplot, I use

cs2=m[1].contourf(x,y,areaData,cmap=cs.cmap)

And for each subsequent subplot, I use

m[ind].contourf(x,y,areaData,cmap=cs.cmap,levels=cs2.levels

where areaData is recalculated within a loop.

My question is, how can I force the first subplot to have the same colors as the other subplots? I am looking for an equivalent to the levels=cs2.levels keyword argument.

Answer 1

As you noted in a comment, your scatter and contour data are not directly related, but you want to display them on the same colormap.

I suggest setting a common colour span that contains both sets of data. Since obsData refers to the scatter points and areaData to the contours, I'd set

vmin,vmax = (fun(np.concatenate([obsData,areaData])) for fun in (np.min,np.max))

to determine the span of the collected data set (obviously, to be generalized for multiple input data sets). These can be passed to scatter and contourf to set the limits of the colour mapping:

cs = m[0].scatter(xs,ys,c=obsData,cmap=plt.cm.viridis,vmin=vmin,vmax=vmax)
cs2 = m[1].contourf(x,y,areaData,cmap=cs.cmap,vmin=vmin,vmax=vmax)

Some manual increase of the span might be in order to obtain a pretty result.

Note that I changed the colormap to viridis . If you really want to fairly represent your data, this should be your first step .