Constraints

A constraint is a logic formula defining allowed combinations of values for a set of variables (see Variables), i.e., restrictions over variables that must be respected in order to get a feasible solution. A constraint is equipped with a (set of) filtering algorithm(s), named propagator(s). A propagator removes, from the domains of the target variables, values that cannot correspond to a valid combination of values. A solution of a problem is a variable-value assignment verifying all the constraints.

Constraints are directly declared from a Model object (see Model).

Integer and boolean constraints

All constraints over integer and boolean variables are declared in the IntConstraintFactory abstract class, which is implemented by the Model class.

absolute

all_different

all_different_except_0

all_different_prec

all_equal

among

and 

argmax

argmin

arithm

at_least_n_values

at_most_n_values

bin_packing

bits_int_channeling

bools_int_channeling

circuit

clauses_int_channeling

cost_regular

count

cumulative

decreasing

diff_n

distance

div

element

global_cardinality

increasing

int_value_precede_chain

inverse_channeling

keysort

knapsack

lex_chain_less

lex_chain_less_eq

lex_less

lex_less_eq

max

mddc

member

min

mod

multi_cost_regular

n_values

not 

not_all_equal

not_member

or 

path

pow

regular

scalar

sort

square

sub_circuit

sub_path

sum

table

times

tree

Set constraints

All constraints over set variables in the SetConstraintFactory abstract class, which is implemented by the Model class. Set constraints have the set_ prefix, indeed, as several set constraints have the same name as int constraints, we made the choice to semantically distinguish them, contrarily to the Choco Java API, as method Python does not support method overloading.

set_all_different

set_all_disjoint

set_all_equal

set_bools_channeling

set_disjoint

set_element

set_intersection

set_ints_channeling

set_inverse_set

set_le

set_lt

set_max

set_max_indices

set_member_int

set_member_set

set_min

set_min_indices

set_nb_empty

set_not_empty

set_not_member_int

set_offset

set_partition

set_subset_eq

set_sum

set_sum_element

set_symmetric

set_union

set_union_indices

Graph constraints

All constraints over graph variables in the GraphConstraintFactory abstract class, which is implemented by the Model class. Graph constraints have the graph_ prefix, indeed, as method Python does not support method overloading, we made the choice to semantically distinguish them to avoid method name conflicts.

graph_anti_symmetric

graph_biconnected

graph_connected

graph_cycle

graph_degrees

graph_diameter

graph_directed_forest

graph_directed_tree

graph_edge_channeling

graph_forest

graph_in_degrees

graph_loop_set

graph_max_degree

graph_max_degrees

graph_max_in_degree

graph_max_in_degrees

graph_max_out_degree

graph_max_out_degrees

graph_min_degree

graph_min_degrees

graph_min_in_degree

graph_min_in_degrees

graph_min_out_degree

graph_min_out_degrees

graph_nb_cliques

graph_nb_connected_components

graph_nb_edges

graph_nb_loops

graph_nb_nodes

graph_nb_strongly_connected_components

graph_neighbors_channeling

graph_no_circuit

graph_no_cycle

graph_node_channeling

graph_node_neighbors_channeling

graph_node_predecessors_channeling

graph_node_successors_channeling

graph_nodes_channeling

graph_out_degrees

graph_reachability

graph_size_connected_components

graph_size_max_connected_components

graph_size_min_connected_components

graph_strongly_connected

graph_subgraph

graph_successors_channeling

graph_symmetric

graph_transitivity

graph_tree