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Mosel NL examples
=================
file airport_nl_graph.mos
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Locate N airports each within a specified distance of a
city centre, and minimise the sum of square of the distances
between all the airports.
QCQP problem.
Based on AMPL model airport.mod by Hande Y. Benson
Source: http://www.orfe.princeton.edu/~rvdb/ampl/nlmodels/cute/
Reference:
Rodrigo de Barros Nabholz & Maria Aparecida Diniz Ehrhardt
November 1994, DMA - IMECC- UNICAMP.
- XNLP version, graph drawing -
(c) 2008 Fair Issac Corporation
author: S. Heipcke, May 2008, rev. Sep. 2017
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model "airport"
uses "mmxnlp", "mmsvg"
declarations
RN: range ! Set of airports
R: array(RN) of real ! Square of max. distance to given location
CX,CY: array(RN) of real ! Target location for each point
x,y: array(RN) of mpvar ! x-/y-coordinates to determine
end-declarations
initialisations from "airport.dat"
CY CX R
end-initialisations
! Set bounds on variables
forall(i in RN) do
-10<=x(i); x(i)<=10
-10<=y(i); y(i)<=10
end-do
! Objective: minimise the total squared distance between all points
TotDist:= sum(i,j in RN | i