AIRPORT
nco
Knitro
AMPL
short
= -10;
var y{1..N} <= 10, >= -10;
minimize f:
sum {i in 1..N-1, j in i+1..N} ( (x[i]-x[j])^2 + (y[i]-y[j])^2 );
subject to cons1 {i in 1..N}:
(x[i]-cx[i])^2 + (y[i]-cy[i])^2 - r[i] <= 0;
]]>
data;
param r:=
1 0.09
2 0.3
3 0.09
4 0.45
5 0.5
6 0.04
7 0.1
8 0.02
9 0.02
10 0.07
11 0.4
12 0.045
13 0.05
14 0.056
15 0.36
16 0.08
17 0.07
18 0.36
19 0.67
20 0.38
21 0.37
22 0.05
23 0.4
24 0.66
25 0.05
26 0.07
27 0.08
28 0.3
29 0.31
30 0.49
31 0.09
32 0.46
33 0.12
34 0.07
35 0.07
36 0.09
37 0.05
38 0.13
39 0.16
40 0.46
41 0.25
42 0.1;
param cx:=
1 -6.3
2 -7.8
3 -9.0
4 -7.2
5 -5.7
6 -1.9
7 -3.5
8 -0.5
9 1.4
10 4.0
11 2.1
12 5.5
13 5.7
14 5.7
15 3.8
16 5.3
17 4.7
18 3.3
19 0.0
20 -1.0
21 -0.4
22 4.2
23 3.2
24 1.7
25 3.3
26 2.0
27 0.7
28 0.1
29 -0.1
30 -3.5
31 -4.0
32 -2.7
33 -0.5
34 -2.9
35 -1.2
36 -0.4
37 -0.1
38 -1.0
39 -1.7
40 -2.1
41 -1.8
42 0.0;
param cy:=
1 8.0
2 5.1
3 2.0
4 2.6
5 5.5
6 7.1
7 5.9
8 6.6
9 6.1
10 5.6
11 4.9
12 4.7
13 4.3
14 3.6
15 4.1
16 3.0
17 2.4
18 3.0
19 4.7
20 3.4
21 2.3
22 1.5
23 0.5
24 -1.7
25 -2.0
26 -3.1
27 -3.5
28 -2.4
29 -1.3
30 0.0
31 -1.7
32 -2.1
33 -0.4
34 -2.9
35 -3.4
36 -4.3
37 -5.2
38 -6.5
39 -7.5
40 -6.4
41 -5.1
42 0.0;
This problem is AIRPORT from the CUTEr collection.