isorange, isovalue

using AbstractPlotting

r = range(-1, stop = 1, length = 100)
matr = [(x.^2 + y.^2 + z.^2) for x = r, y = r, z = r]
volume(matr .* (matr .> 1.4), algorithm = :iso, isorange = 0.05, isovalue = 1.7)