| % File src/library/datasets/man/rock.Rd |
| % Part of the R package, https://www.R-project.org |
| % Copyright 1994-8 W. N. Venables and B. D. Ripley |
| % Distributed under GPL 2 or later |
| |
| % Manually converted to Rd data file description format by KH. |
| \name{rock} |
| \docType{data} |
| \alias{rock} |
| \title{Measurements on Petroleum Rock Samples} |
| \description{ |
| Measurements on 48 rock samples from a petroleum reservoir.} |
| \usage{rock} |
| \format{ |
| A data frame with 48 rows and 4 numeric columns. |
| |
| \tabular{rll}{ |
| [,1] \tab area \tab area of pores space, in pixels |
| out of 256 by 256 \cr |
| [,2] \tab peri \tab perimeter in pixels \cr |
| [,3] \tab shape \tab perimeter/sqrt(area) \cr |
| [,4] \tab perm \tab permeability in milli-Darcies |
| } |
| } |
| \details{ |
| 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. |
| } |
| \source{ |
| Data from BP Research, image analysis by Ronit Katz, U. Oxford. |
| } |
| \keyword{datasets} |