added tests

src/problems.jl

@@ -5,22 +5,72 @@ abstract Problem
 abstract BoundaryProblem <: Problem
 abstract FieldProblem <: Problem
 
+""" Return all equations beloging to this problem. """
 function get_equations(problem::Problem)
     problem.equations
 end
 
+""" Return the dimension of the unknown field of this problem. """
 function get_unknown_field_dimension(problem::Problem)
     problem.unknown_field_dimension
 end
 
+""" Return the name of the unknown field of this problem. """
 function get_unknown_field_name(problem::Problem)
     problem.unknown_field_name
 end
 
-""" Add new element to problem. """
+"""
+Add new equation to problem.
+
+Parameters
+----------
+problem
+element
+
+Notes
+-----
+Equation is automatically created during process based on problem
+element -> equation mapping and element type.
+"""
 function Base.push!(problem::Problem, element::Element)
     element_type = typeof(element)
     equation_type = problem.element_mapping[element_type]
     push!(problem.equations, equation_type(element))
 end
 
+"""
+Return the size of the problem, i.e.
+maximum number of connectivity × unknown field dimension.
+"""
+function Base.size(problem::Problem)
+    mc = 0
+    for equation in get_equations(problem)
+        element = get_element(equation)
+        mc = max(mc, get_connectivity(element)...)
+    end
+    dim = get_unknown_field_dimension(problem)
+    return (dim, dim*mc)
+end
+
+""" Assign new equation mapping to problem for some element.
+
+Examples
+--------
+>>> p = PlaneHeatProblem()
+>>> p[Seg2] = DC2D2
+
+"""
+function Base.setindex!(problem::Problem, equation, element)
+    problem.element_mapping[element] = equation
+end
+
+""" Return global degrees of freedom of element in matrix level. """
+function get_gdofs(problem::Problem, equation::Equation)
+    dim = get_unknown_field_dimension(problem)
+    element = get_element(equation)
+    conn = get_connectivity(element)
+    gdofs = vec(vcat([dim*conn'-i for i=dim-1:-1:0]...))
+    return gdofs
+end
+