DISCLA Process
To access this process:
- Sample Analysis ribbon >> Geochemical Processes >> Multiple Discriminant Classify.
- View the Find Command screen, select DISCLA and click Run.
- Enter "DISCLA" into the Command Line and press <ENTER>.
See this process in the Command Table.
Process Overview
Multiple discriminant classification of unknown samples into groups using the discriminant functions and group centroids calculated in the DISCAN process.
Discriminant analysis is a classification problem, where two or more groups or clusters or populations are known a priori and one or more new observations are classified into one of the known populations based on the measured characteristics.
Multiple discriminant analysis using trial (test) data sets to calculate scores and discriminant functions with group centroids for use in the DISCLA process.
The calculation of discriminant functions (Discriminant analysis) will establish a set of rules using geological control groups or training sets which can then be applied to the classification of unknown samples using the DISCLA process.
For example, test data from DISCAN will calculate discriminant functions and group centroids to classify known samples into mineralized and non-mineralized. DISCLA will then use the discriminant functions and group centroids and apply them to unknown samples in order to identified them into the classes mineralized and non-mineralized, plus a third class, to include the samples which are not classifiable.
Note: there is a maximum limit of 45 variables and 10 classifier groups with an extra group for non classifiable samples. Samples containing absent data are ignored.
File Handling
The input file (&IN), of samples for classification must contain a sample identifier field (@SAMPID). The input files (&INFUNCTS) discriminant functions and (&INCENTRD) group centroids are obligatory. File &INCENTRD must contain a group identifier specified in @GROUPID. The output file of classified samples (&OUT) contains a new field named in @GROUPID identifying the group classifier or a flag to note that the sample is not classifiable using the data given in files &INFUNCTS and &INCENTRD.
The output file containing the discriminant scores for each sample can be joined to the original data containing the grid coordinates using the SAMPID as a key field. The scores can then be plotted as a map.
Input Files
|
Name |
Description |
I/O Status |
Required |
Type |
|
IN |
Input file. Must contain sample identity field. |
Input |
Yes |
Undefined |
|
INFUNCTS |
Input file containing discriminant functions. Produced from process DISCAN. |
Input |
Yes |
Undefined |
|
INCENTRD |
Input file containing group centroids. Produced from process DISCAN. Must contain a group identity field specified in GROUPID. |
Input |
Yes |
Undefined |
Output Files
|
Name |
I/O Status |
Required |
Type |
Description |
|
OUT |
Output |
Yes |
Undefined |
Output file containing samples classified into groups identified by the GROUPID field and the discriminant scores.. |
Fields
|
Name |
Description |
Source |
Required |
Type |
Default |
|
GROUPID |
Compulsory group identifier field contained in INCENTRD. |
INCENTRD |
Yes |
Alphanumeric |
Undefined |
|
SAMPID |
Compulsory sample identifier field in input file IN. |
IN |
Yes |
Any |
Undefined |
|
F1 |
First field to be used. No fields specified means all. |
IN |
No |
Numeric |
Undefined |
|
F2 |
Second field to be used. |
IN |
No |
Numeric |
Undefined |
|
F3 |
Third field to be used. |
IN |
No |
Numeric |
Undefined |
|
F4 |
Fourth field to be used. |
IN |
No |
Numeric |
Undefined |
|
F5 |
Fifth field to be used. |
IN |
No |
Numeric |
Undefined |
|
F6 |
Sixth field to be used. |
IN |
No |
Numeric |
Undefined |
|
F7 |
Seventh field to be used. |
IN |
No |
Numeric |
Undefined |
|
F8 |
Eighth field to be used. |
IN |
No |
Numeric |
Undefined |
|
F9 |
Ninth field to be used. |
IN |
No |
Numeric |
Undefined |
|
F10 |
Tenth field to be used. |
IN |
No |
Numeric |
Undefined |
Example
DISCLA! &IN(AREAZ), &INFUNCTS(GGFUNCTS), &INCENTRD(GGCENT), &OUT(AREAZCL), @GROUPID='ID', @SAMPID= 'ID'
Error and Warning Messages
| Message |
|
*** Warning *** GROUPID field has nn words. Only the first 3 will be used. |
|
*** Warning *** SAMPID field has nn words. Only the first 3 will be used. |
|
*** Error *** GROUPID field (fieldname) is not in input file. |
|
*** Error *** No numeric fields on file (filename) >>> ERR 122 <<< ( fileno.) IN DISCLA |
|
*** Error *** SAMPID field (fieldname) is not in input file. |
|
*** Error *** Compulsory file, field or perimeter
missing. |
