SIMSCRIPT II.5 Programming Language

Programming Language Concepts
for I = 1 to N,
compute
MEANX as the mean,
MAXIMUMX as the maximum of X(I)
Like the find statement, the compute statement contains a list of variables that are set to a computed
value after iteration. In this case, the values are specified by statistical names, such as mean
and maximum. A compute statement has the general form:
compute compute list of arithmetic expression
where compute list is a list of variable and statistical names of the form variable =
statistic name. The optional word the may be omitted before each statistic name, and the word
as may be replaced by the equal sign. A compute statement can be controlled by more than one
for phrase, and these may use logical control phrases to qualify the iteration sequence or the
selection of individual variables. For example:
for I = 1 to N,
for J = 1 to M,
with LIST(J) greater than zero
compute
MN as the mean of TABLE(I,J) * LIST(J)
When a compute statement appears within a do loop with other statements, calculation of computed
statistics, such as mean, takes place at the loop statement. If, for some reason, control is transferred
out of the loop, the statistics are undefined. In the following example, computation of the
indicated statistics is executed at termination of the inner do loop. Within this loop, the values
X(J) are summed, and a count accumulated of the number of elements that form this sum. Before
statement 4 is executed, these two values are used to compute the mean.
for I = 1 to N,
do
statement1
for J = 1 to M,
do
statement2
compute
MEANX as the mean of X(J)
statement3
loop
statement4
loop
Within the inner loop, the value of MEANX is undefined.
To have a compute statement controlled by several control phrases, a program is written with
also phrases, as:
101