transD_GP.getchi2forall(opt, nxticks=4, fsize=6)
ax = gcf().axes;
ax[2].set_ylim(10, 30)
opt.xall[:] .= zall
transD_GP.plot_posterior(tempest, opt, burninfrac=0.5, figsize=(4,4),
    cmappdf="inferno", qp1=0.01, qp2=0.99)
step(log10.(ρ[2:end]), z[2:end], color="w", alpha=0.4)
##
gcf()
