The Selected Area Factoring option within MX factors an area defined by an upper and lower row (i.e., origin) plus a left-hand and right-hand column (i.e., destination) by a specific factor. They therefore define a “rectangular” sub-area within the full matrix “square”. (And indeed it may help users to draw a “map” of the matrix and its sub-areas, a bit like a Venn diagram, in order to help visualise what is included in each sub-area, whether there are overlaps (allowed), etc. etc.)
The external control file defines areas plus factors formatted as follows, one record per area to be factored:
|
Cols. |
1 - 5 |
Upper row |
|
Cols. |
6 - 10 |
Lower row |
|
Cols. |
11 - 15 |
Left-hand column |
|
Cols. |
16 - 20 |
Right-hand column |
|
Cols. |
21 - 30 |
Factor - decimal normally in column 28 (Format F10.2) |
Certain options for the definition of the row and column factors may be selected interactively before the file is processed. (N.B. Mixing interactive and file input control is not ideal but it works and given how infrequently this method is probably used it doesn’t seem worth introducing major changes; requests to DVV!)
Thus, rows and columns may be defined as either names or sequential numbers via an option set interactively prior to processing the file. Names are then re-set to the equivalent sequential values.
Similarly for stacked matrices the row and column numbers may be based either on the full matrix or for a particular level within the stacked matrix. For example, if one had 3 10x10 matrices stacked (so that the internal matrix has 30 rows and 10 columns) and one wished to factor rows 3 to 5 of level 2 then one could either specify them as (sequential) rows 13 to 15 if a level were unset or rows 3 to 5 if the level were pre-defined as 2.
Note that if the option to use zone names rather than sequential numbers has been pre-selected then the only way to define rows within levels other than the first is to pre-define the level.
Row or column numbers left blank (or equal to zero) are assumed to be either 1 or the maximum row/column number as appropriate. Hence all blanks in columns 1 to 20 implies the whole matrix is to be factored. Using blanks or zeros as inputs is generally not recommended for matrices with multiple levels and/or blocks as it easy to get confused; it is best to be explicit.
To terminate the file put 99999 in columns 1 to 5 - or, strictly, any number or name greater than the number of rows.
Alternatively the input data may be free format - again, a user-set option - in which case each of the five inputs must be separated by blanks or commas.