AMPL duplicate member "x" for set "y", how to fix it

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Hi @Ares_Inglada_Grano,

Without specifying the arity of a set it defaults to 1 and any repeated value in the data section will then be a duplicate. You need to specify the arity of the set (i.e., set path_intersections dimen 2;) as follows:

set path_intersections dimen 2;
data;
set path_intersections := 
1439 5
1439 74243
1441 5
1441 89
1441 90;
display path_intersections;

This will produce the following output:

set path_intersections :=
(1439,5)       (1439,74243)   (1441,5)       (1441,89)      (1441,90);

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