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Set Constructor Expression
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- { [ expression-1 [, ...expression-n] ] } ;
The set constructor expression returns the set of the expressions in the member list. Duplicated values are added to the set only once. A warning message is produced when duplicates are detected. The constructor expression consists of 0 or more subexpressions of the same scalar type or of tuple expressions that match in length and in element types.
The following code outputs a three-member set and warns about the duplicated value 2:
proc optmodel;
put ({1,2,3,2}); /* outputs {1,2,3} */
The following example produces a three-member set of tuples, using PROC OPTMODEL parameters and variables. The output is displayed in Figure 8.31.
proc optmodel;
number m = 3, n = 4;
var x{1..4} init 1;
string y = 'c';
put ({<'a', x[3]>, <'b', m>, <y, m/n>});
Figure 8.31
Set Constructor Expression Output
{<'a',1>,<'b',3>,<'c',0.75>}
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