add choose!

don't add XOR with reformulation

Author: hdavid16

src/DisjunctiveProgramming.jl

@@ -4,6 +4,7 @@ using JuMP, IntervalArithmetic, Symbolics, Suppressor
 
 export add_disjunction!, add_proposition!, reformulate_disjunction
 export @disjunction, @proposition
+export choose!
 
 include("constraint.jl")
 include("logic.jl")

src/logic.jl

@@ -1,8 +1,28 @@
 """
+    choose!(m::Model, n::Int, vars::VariableRef...; mode)
 
+Add constraint to select n elements from the list of variables. Options for mode
+are `:at_least`, `:at_most`, `:exactly`.
 """
-function select()
-    
+function choose!(m::Model, n::Int, vars::VariableRef...; mode=:exactly)
+    @assert length(vars) >= n "Not enough variables passed."
+    @assert all(is_valid.(m, vars)) "Invalid VariableRefs passed."
+    add_selection!(m, n, vars...; mode)
+end
+function choose!(m::Model, vars::VariableRef...; mode=:exactly)
+    @assert all(is_valid.(m, vars)) "Invalid VariableRefs passed."
+    n = vars[1] #first variable is the n
+    add_selection!(m, n, vars...; mode)
+end
+function add_selection!(m::Model, n, vars::VariableRef...; mode::Symbol)
+    display(n)
+    if mode == :exactly
+        display(@constraint(m, sum(vars) == n))
+    elseif mode == :at_least
+        @constraint(m, sum(vars) ≥ n)
+    elseif mode == :at_most
+        @constraint(m, sum(vars) ≥ n)
+    end
 end
 
 """

src/macros.jl

@@ -50,14 +50,14 @@ macro disjunction(m, args...)
         end
     end
 
-    #XOR constraint name
-    xor_con = Symbol("XOR($disj_name)")
+    # #XOR constraint name
+    # xor_con = Symbol("XOR($disj_name)")
 
     #build disjunction
     code = quote
         @assert !in($name, keys(object_dictionary($m))) "The disjunction name $name is already registered in the model. Specify new name."
         $m[$name] = @variable($m, [eachindex($disjunction)], Bin, base_name = string($name), lower_bound = 0, upper_bound = 1)
-        @constraint($m, $xor_con, sum($m[$name]) == 1)
+        # @constraint($m, $xor_con, sum($m[$name]) == 1)
         reformulate_disjunction($m, $(disjunction...); bin_var = $name, reformulation = $reformulation, param = $param)
     end
 
@@ -114,15 +114,15 @@ function add_disjunction!(m::Model,disj...;reformulation::Symbol,M=missing,ϵ=1e
     bin_var = ismissing(name) ? Symbol("disj",gensym()) : name
     disj_name = ismissing(name) ? bin_var : Symbol("disj_",name)
 
-    #XOR constraint name
-    xor_con = "XOR($disj_name)"
+    # #XOR constraint name
+    # xor_con = "XOR($disj_name)"
 
     #apply reformulation
     @assert !in(bin_var, keys(object_dictionary(m))) "The disjunction name $bin_var is already registered in the model. Specify new name."
     #create indicator variable
     m[bin_var] = @variable(m, [eachindex(disj)], Bin, base_name = string(bin_var), lower_bound = 0, upper_bound = 1)
-    #add xor constraint on binary variable
-    m[Symbol(xor_con)] = @constraint(m, sum(m[bin_var]) == 1, base_name = xor_con)
+    # #add xor constraint on binary variable
+    # m[Symbol(xor_con)] = @constraint(m, sum(m[bin_var]) == 1, base_name = xor_con)
     #reformulate disjunction
     reformulate_disjunction(m, disj...; bin_var, reformulation, param)
 end

src/reformulate.jl

@@ -30,7 +30,7 @@ function reformulate_disjunction(m::Model, disj...; bin_var, reformulation, para
     new_constraints = Dict{Symbol,Any}(
         Symbol(bin_var,"[$i]") => disj[i] for i in eachindex(disj)
     )
-    new_constraints[Symbol(bin_var,"_XOR")] = constraint_by_name(m, "XOR(disj_$bin_var)")
+    # new_constraints[Symbol(bin_var,"_XOR")] = constraint_by_name(m, "XOR(disj_$bin_var)")
     if reformulation == :hull
         for var in m[:gdp_variable_refs]
             agg_con_name = "$(var)_$(bin_var)_aggregation"