If an array of decision variables of type mpvar is created as a dynamic array then its entries must be created explicitly using the subroutine create (doesx.mos). It is recommended to add an explicit 'exists' condition in loops over sparse arrays to improve the performance of the enumeration (doesx1.mos). Through the automatic finalization mechanism or via an explicit call to finalize a dynamic set is turned into a constant set, all subsequently declared arrays that are indexed by this set will be created as static arrays (doesx2.mos).
(!******************************************************
Mosel User Guide Example Problems
=================================
file doesx.mos
``````````````
Working with dynamic arrays of variables.
(c) 2008 Fair Isaac Corporation
author: Bob Daniel, 2001, rev. Sep. 2018
*******************************************************!)
model doesx
public declarations
IR = 1..15
WHICH: set of integer
x: dynamic array(IR) of mpvar
Obj,C: linctr
end-declarations
! Read data from file
initializations from 'doesx.dat'
WHICH
end-initializations
! Create the x variables that exist
forall(i in WHICH) create(x(i))
! Build a little model to show what esists
Obj:= sum(i in IR) x(i)
C:= sum(i in IR) i * x(i) >= 5
exportprob(0, "", Obj) ! Display the resulting problem definition in Mosel
end-model
(!******************************************************
Mosel User Guide Example Problems
=================================
file doesx1.mos
```````````````
Working with dynamic arrays of variables.
-- Using 'exists' in enumerations --
(c) 2008 Fair Isaac Corporation
author: Bob Daniel, 2001, rev. Nov. 2021
*******************************************************!)
model doesx1
public declarations
IR = 1..15
WHICH: set of integer
x: dynamic array(IR) of mpvar
Obj,C: linctr
end-declarations
! Read data from file
initializations from 'doesx.dat'
WHICH
end-initializations
! Create the x variables that exist
forall(i in WHICH) create(x(i))
! Build a little model to show what esists
Obj:= sum(i in IR | exists(x(i))) x(i)
C:= sum(i in IR | exists(x(i))) i * x(i) >= 5
exportprob(0, "", Obj) ! Display the resulting problem definition in Mosel
end-model
(!******************************************************
Mosel User Guide Example Problems
=================================
file doesx2.mos
```````````````
Using 'finalize' to turn a dynamic set into
a constant set.
(c) 2008 Fair Isaac Corporation
author: Bob Daniel, 2001, rev. Sep. 2021
*******************************************************!)
model doesx2
public declarations
WHICH: set of integer
Obj,C: linctr
end-declarations
initializations from 'doesx.dat'
WHICH
end-initializations
public declarations
x: array(WHICH) of mpvar ! Here the array is _not_ dynamic
end-declarations ! because the set has been finalized
Obj:= sum(i in WHICH) x(i)
C:= sum(i in WHICH) i * x(i) >= 5
exportprob(0, "", Obj) ! Display the resulting problem definition in Mosel
end-model
