This page contains an explanation of many of the terms used by the Particle-Size Toolbox.


EPS - extended postscript file:
These are high quality vector image files that can be easily edited in Adobe Illustrator or Corel Draw.

Log-ratio transform - converts compositional data into Euclidean space
A log-ratio transform removes the dual constraints operating on particle-size distribution, namely that the values sum to a constant and that they are all positive. There are a few different types of log-ratio transform. In the Particle-Size Toolbox the additive log-ratio (alr) and the centred log-ratio (clr) are both used. For a D-part composition p, the alr transform is:

external image gif.latex?%5Cfn_cm&space;q_i&space;=&space;ln%5Cleft(%5Cfrac%7Bp_i%7D%7Bp_D%7D%5Cright)

and the clr transform is:
clr.gif

Logfile - a record of actions
Log files are text files that contain a record of each higher-level function performed by a PST project and where the results are stored.

Pfile - parameter file
Parameter file contain data about each Particle-Size Toolbox project, e.g. the directory structure, file types and what processes have already occurred.

timeANDdate - a file identifier showing the tim and date when a file is created.