out =
rock ()
¶Measurements on Petroleum Rock Samples
Measurements on 48 rock samples from a petroleum reservoir.
area
Area of pores space, in pixels out of 256 by 256.
peri
Perimeter in pixels.
shape
Perimeter/sqrt(area).
perm
Permeability in milli-Darcies.
Twelve core samples from petroleum reservoirs were sampled by 4 cross-sections. Each core sample was measured for permeability, and each cross-section has total area of pores, total perimeter of pores, and shape.
Data from BP Research, image analysis by Ronit Katz, U. Oxford.
t = octave.dataset.rock; figure scatter (t.area, t.perm) xlabel ("Area of pores space (pixels out of 256x256)") ylabel ("Permeability (milli-Darcies)")