Set

class Set : public ampl::BasicEntity<SetInstance>

Represents an AMPL set.

In case of not indexed sets, this class exposes iterators for accessing its elements. The members of the set are tuples, represented by objects of class ampl::Tuple.

All these methods throw an std::logic_error if called for an indexed set.

In case of indexed sets, you can gain access to the instances (of class ampl::SetInstance) using the methods Set::get(), using the operator Set::operator[]() or via Set::instances(), which returns an InstanceRange providing iterators.

Data can be assigned to the set using the methods Set::setValues (for non-indexed sets only) or using ampl::setData and an object of class ampl::DataFrame.

Instance access

Methods to access the instances which are part of this Entity

SetInstance get() const

Get the instance corresponding to a scalar entity.

Return

The corresponding instance.

Exceptions

• runtime_error: if the entity has been deleted in the underlying AMPL interpreter
• logic_error: if the entity is not scalar

SetInstance get(TupleRef index) const

Get the instance with the specified index.

Return

The corresponding instance

Parameters

• index: The tuple specifying the index

Exceptions

• out_of_range: if an instance with the specified index does not exist
• out_of_range: if the entity has been deleted in the underlying AMPL interpreter
• ampl::UnsupportedOperationException: if the entity is scalar

SetInstance get(VariantRef v1) const

Get the instance with the specified index.

SetInstance get(VariantRef v1, VariantRef v2) const

Get the instance with the specified index.

SetInstance get(VariantRef v1, VariantRef v2, VariantRef v3) const

Get the instance with the specified index.

SetInstance get(VariantRef v1, VariantRef v2, VariantRef v3, VariantRef v4) const

Get the instance with the specified index.

Return

The corresponding instance

Parameters

• v1: The VariantRef specifying the first element of the indexing tuple
• v2: The VariantRef specifying the second element of the indexing tuple
• v3: The VariantRef specifying the third element of the indexing tuple
• v4: The VariantRef specifying the fourth element of the indexing tuple

Exceptions

• out_of_range: if an instance with the specified index does not exist
• runtime_error: if the entity has been deleted in the underlying AMPL interpreter
• ampl::UnsupportedOperationException: if the entity is scalar

SetInstance operator[](TupleRef index) const

SetInstance operator[](VariantRef v1) const

Public Types

typedef SetInstance::MemberRange MemberRange

Class to access the members of this set (valid only for non-indexed sets)

typedef internal::CountedIterator<internal::EntityWrapper<SetInstance>> iterator

Iterator for entities, represented by an iterator pointing to elements of type std::pair<TupleRef, InstanceClass>

Public Functions

InstanceRange instances() const

Get the InstanceRange used to iterate over all the instances in a Set.

std::size_t arity() const

The arity of s, or number of components in each member of this set.

DataFrame getValues() const

Get values of this set in a DataFrame.

Valid only for non indexed sets.

See

SetInstance::getValues()

MemberRange members() const

Get of this Set.

Valid only for non indexed sets.

See

SetInstance::members()

std::size_t size() const

Get the number of tuples in this set.

Valid only for non indexed sets.

bool contains(TupleRef t) const

Check wether this set instance contains the specified Tuple.

Valid only for non indexed sets.

Parameters

• t: Tuple to be found

void setValues(internal::Args objects, std::size_t n)

Set values.

Valid only for non indexed sets.

See

SetInstance::setValues()

void setValues(const Tuple objects[], std::size_t n)

Set values.

Valid only for non indexed sets.

See

SetInstance::setValues()

void setValues(DataFrame data)

Set values.

Valid only for non indexed sets.

See

SetInstance::setValues()

iterator begin()

Get an iterator pointing to the first instance in this entity.

iterator end()

Get an iterator pointing after the last instance in this entity.

iterator find(TupleRef t) const

Searches the current entity for an instance with the specified index.

Return

an iterator to the wanted entity if found, otherwise an iterator to BasicEntity::end.

DataFrame getValues()

Get the principal values of this entity as a DataFrame. The specific returned value depends on the type of entity (see list below).

For:

• Variables and Objectives it returns the suffix val
• Parameters it returns their values
• Constraints it returns the suffix dual
• Sets it returns all the of the set. Note that it does not
• apply to indexed sets. See SetInstance::getValues

Return

A DataFrame containing the values for all instances

void setValues(DataFrame data)

Set the values of this entiy to the correponding values of a DataFrame indexed over the same sets (or a subset). This function assigns the values in the first data column of the passed dataframe to the entity the function is called from. In particular, the statement:

x.setValues(y.getValues());

is semantically equivalent to the AMPL statement:

let {s in S} x[s] := y[s];

Parameters

• data: The data to set the entity to

StringArray getIndexingSets()

Get the AMPL string representation of the sets on which this entity is indexed.

The obtained vector can be modified without any effect to the entity.

Return

The string representation of the indexing sets for this entity or an empty array if the entity is scalar

std::string name()

Get the name of this entity.

std::size_t indexarity()

Get the indexarity of this entity (sum of the dimensions of the indexing sets).

This value indicates the arity of the Tuple to be passed to the method BasicEntity::get() in order to access an instance of this entity. See the following AMPL examples

var x;               # indexarity = 0
var y {1..2};        # indexarity = 1
var z {1..2,3..4};   # indexarity = 2
var zz {{(1, 2)}};   # indexarity = 2

Return

The sum of the dimensions of the indexing sets or 0 if the entity is not indexed

bool isScalar()

Check whether this entity is scalar.

Equivalent to testing whether indexarity() is equal to zero.

Return

True if the entity is scalar (not indexed over any set)

std::string toString()

Returns a string representation of this entity (its declaration)

std::size_t numInstances()

Get the number of instances in this entity.

class InstanceRange

Class used to iterate over all the instances of a Set. For example, supposing an indexed set set A{1..2}; is defined in an AMPL object named ampl:

ampl::Set A = ampl.getSet("A");
for (ampl::SetInstance s: A.instances())
  std::cout << s.name() << "\n";

Public Types

typedef Set::iterator iterator

Iterator over instances of an indexed set.

Public Functions

iterator begin() const

Get an iterator pointing to the first instance in this set.

iterator end() const

Get an iterator pointing after the last instance in this entity.

iterator find(TupleRef t) const

Searches the current entity for an instance with the specified index.

Return

an iterator to the SetInstance if found, otherwise InstanceRange::end.