Select color range for heatmap

[rafael.guerra]

Not mapping exactly 0 to green but all floats between -1 and 0 as per your wishes:

using Plots; gr()
m = -2000*(rand(200,200))
c = cgrad([:red,:yellow,:green], [0.50, 0.9995], categorical = true)
heatmap(m, color=c, clim=(-2000,0))