R- or C-cell

 Word Use

 5 Incidence count

 6 Various

The first word serves as a pointer to an H- (for R-cells) or V- (for

C-cells) cell. The H- and V-cells are discussed later. The status flag

indicates such things as whether the row or column is output set

assigned, a decision, or to be ignored. The words marked "various"

have different uses in different applications. The output pointer is a

pointer to the C-cell (for R-cells) or R-cell (for C-cells) which

represents the output of the R- or C-cell in question. The incidence

count indicates the number of elements in the row or column in question.

 As was indicated, each R- and C-cell has a pointer to an H- or

V-cell. The H- and V-cells are similar in structure, so only the H-cell

will be discussed. Each H-cell has a variable length, which is indi-

cated by the first word of the cell. The remaining words of the H-cell

each point to a different E-cell. The H-cell, then, provides a set of

pointers to E-cells for each of the R-cells.

 As might be expected, the E-cells represent the actual elements

of the SIM. They are each pointed to by an element of an H-cell and

an element of a V-cell. E-cells all have the same length, which, like

R- and C-cells', can vary from application to application. The length

of an E-cell must be at least three words. The first is a pointer to

the R-cell representing the row which contains the element. The second

word is a pointer to the C-cell representing the column which contains

the element. The third word contains data (e.g., weight) associated

with the element.