Merge pull request #7 from xtalax/observed

Add observed variable defaults

Author: YingboMa

src/SymbolicIndexingInterface.jl

@@ -6,6 +6,8 @@ include("interface.jl")
 include("symbolcache.jl")
 
 export independent_variables, is_indep_sym, states, state_sym_to_index, is_state_sym,
-       parameters, param_sym_to_index, is_param_sym, SymbolCache
+       parameters, param_sym_to_index, is_param_sym, observed, observed_sym_to_index,
+       is_observed_sym, get_state_dependencies, get_observed_dependencies,
+       get_deps_of_observed, SymbolCache, unknown_states
 
 end

src/interface.jl

@@ -31,6 +31,15 @@ states(::Any) = []
 """
 $(TYPEDSIGNATURES)
 
+Get an iterable over the unknown states for the given system. Default to an empty vector.
+"""
+function unknown_states end
+
+unknown_states(::Any) = []
+
+"""
+$(TYPEDSIGNATURES)
+
 Find the index of the given sym in the given system. Default to the index of the first
 symbol in the iterable returned by `states` which matches the given `sym`. Return
 `nothing` if the given `sym` does not match.
@@ -81,3 +90,73 @@ to checking if the value returned by `param_sym_to_index` is not `nothing`.
 function is_param_sym end
 
 is_param_sym(store, sym) = !isnothing(param_sym_to_index(store, sym))
+
+"""
+$(TYPEDSIGNATURES)
+
+Get an iterable over the observed variable expressions for the given system.
+Default to an empty vector.
+"""
+function observed end
+
+observed(::Any) = []
+
+"""
+$(TYPEDSIGNATURES)
+
+Check if the given sym is an observed variable in the given system. Default
+to checking if the value returned by `observed_sym_to_index` is not `nothing`.
+"""
+function is_observed_sym end
+
+is_observed_sym(store, sym) = !isnothing(observed_sym_to_index(store, sym))
+
+"""
+$(TYPEDSIGNATURES)
+
+Find the index of the given sym in the given system. Default to the index of the first
+symbol in the iterable returned by `states` which matches the given `sym`. Return
+`nothing` if the given `sym` does not match.
+"""
+function observed_sym_to_index end
+
+function observed_sym_to_index(store, sym)
+    findfirst(o -> isequal(sym, o.lhs), observed(store))
+end
+
+"""
+$(TYPEDSIGNATURES)
+
+Return a list of the dependent state variables of an observed variable. Default to returning
+an empty list.
+"""
+function get_state_dependencies end
+
+get_state_dependencies(store, sym) = []
+
+"""
+$(TYPEDSIGNATURES)
+
+Return a list of the dependent observed variables of an observed variable. Default to returning
+an empty list.
+"""
+function get_observed_dependencies end
+
+get_observed_dependencies(store, sym) = []
+
+"""
+$(TYPEDSIGNATURES)
+
+Return a list of the dependent state variables of all observed equations of the system.
+Default to returning an empty list.
+"""
+function get_deps_of_observed end
+
+function get_deps_of_observed(store)
+    obs = observed(store)
+    deps = mapreduce(vcat, obs, init = []) do eq
+        get_state_dependencies(store, eq.lhs)
+    end |> unique
+
+    return deps
+end

test/default_function_test.jl

@@ -3,8 +3,13 @@ using SymbolicIndexingInterface, Test
 @test independent_variables(nothing) == []
 @test states(nothing) == []
 @test parameters(nothing) == []
+@test observed(nothing) == []
 @test !is_indep_sym(nothing, :a)
 @test !is_state_sym(nothing, :a)
 @test !is_param_sym(nothing, :a)
+@test !is_observed_sym(nothing, :a)
 @test isnothing(state_sym_to_index(nothing, :a))
 @test isnothing(param_sym_to_index(nothing, :a))
+@test get_state_dependencies(nothing, :a) == []
+@test get_observed_dependencies(nothing, :a) == []
+@test get_deps_of_observed(nothing) == []