status, l=tagged. The return code from JB1TA may indicate success,

failure, or that two-way edges need their tear choices reversed. When

a Boolean sum of rows or columns is performed, the subroutine INSERT is

called to insert elements into the SIM. Should two-way edge tears need

to be reversed, the function J1CTWE is employed in tracing the two-way

edge links to determine which two-way edge must be altered. This is

indicated upon return from J1BTA.

8.4.3 J1LNKC

J1CTWE (5.2)

 As two-way edges are discovered, the rows and columns (functions

and variables) involved are linked together. A two-way edge may have

several columns as complements to a single row. These are linked by a

circular list, the R-cell for the complement row pointing into this

list. This is complicated by the fact that columns can be in more than

one circular list. The subroutine JILNKC is called whenever a column

is to be added to a circular list. Multiple pointers are accomodated

by using auxiliary storage space not in the C-vector.

B.4.4 MEMSTR

NAMGEN (5.8), WRTDSK (6.22)

 The function MEMSTR is invoked to find the beginning address in

MEMORY into which data can be stored. Its value upon return is either

that beginning address or zero, which indicates that MEMORY does not

have enough space for the data item. MEMSTR checks the length of the

data item against the available space. If there is enough space the

beginning address is returned. If there isn't enough space W.RTDSK is

called and the available space is again checked. When there is