How to set scientific notation limits for colorbar?-CodePudding

I am trying to put a scientific notation in all ticks of colorbar (the figure below). I could make it by colorbar(cs, format='%.2e'). The problem is that after I set tick labels using the following lines

cbar.set_ticks(levels)
cbar.set_ticklabels(levels)

the lower limit of notation seems to change to -5 and it shows normal digits for -4 like the figure below (note the tick label 0.00036). I know that one can change scientific notation limits for axes through

CodePudding user response：

you can specify the ticks when creating the colorbar, then the cbformat works. IIUC the following plot is what you want:

fig, ax = plt.subplots()
plot = ax.contourf(z, levels, norm=LogNorm())

cbformat = ticker.ScalarFormatter()
cbformat.set_scientific('%.2e')
cbformat.set_powerlimits((-4,12))
cbformat.set_useMathText(True)
cbar = fig.colorbar(plot, ticks=levels, location='right', format=cbformat)

plt.show()