--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/+scheme/bcSetup.m	Fri Sep 07 14:40:58 2018 +0200
@@ -0,0 +1,110 @@
+% function [closure, S] = bcSetup(diffOp, bc)
+% Takes a diffOp and a cell array of boundary condition definitions.
+% Each bc is a struct with the fields
+%  * type     -- Type of boundary condition
+%  * boundary -- Boundary identifier
+%  * data     -- A function_handle for a function which provides boundary data.(see below)
+% Also takes S_sign which modifies the sign of S, [-1,1]
+% Returns a closure matrix and a forcing function S.
+%
+% The boundary data function can either be a function of time or a function of time and space coordinates.
+% In the case where it only depends on time it should return the data as grid function for the boundary.
+% In the case where it also takes space coordinates the number of space coordinates should match the number of dimensions of the problem domain.
+% For example in the 2D case: f(t,x,y).
+function [closure, S] = bcSetup(diffOp, bcs, S_sign)
+    default_arg('S_sign', 1);
+    assertType(bcs, 'cell');
+    assert(S_sign == 1 || S_sign == -1, 'S_sign must be either 1 or -1');
+
+    verifyBcFormat(bcs, diffOp);
+
+    % Setup storage arrays
+    closure = spzeros(size(diffOp));
+    gridData = {};
+    symbolicData = {};
+
+    % Collect closures, penalties and data
+    for i = 1:length(bcs)
+        [localClosure, penalty] = diffOp.boundary_condition(bcs{i}.boundary, bcs{i}.type);
+        closure = closure + localClosure;
+
+        [ok, isSym, data] = parseData(bcs{i}, penalty, diffOp.grid);
+
+        if ~ok
+            % There was no data
+            continue
+        end
+
+        if isSym
+            symbolicData{end+1} = data;
+        else
+            gridData{end+1} = data;
+        end
+    end
+
+    % Setup penalty function
+    O = spzeros(size(diffOp),1);
+    function v = S_fun(t)
+        v = O;
+        for i = 1:length(gridData)
+            v = v + gridData{i}.penalty*gridData{i}.func(t);
+        end
+
+        for i = 1:length(symbolicData)
+            v = v + symbolicData{i}.penalty*symbolicData{i}.func(t, symbolicData{i}.coords{:});
+        end
+
+        v = S_sign * v;
+    end
+    S = @S_fun;
+end
+
+function verifyBcFormat(bcs, diffOp)
+    for i = 1:length(bcs)
+        assertType(bcs{i}, 'struct');
+        assertStructFields(bcs{i}, {'type', 'boundary'});
+
+        if ~isfield(bcs{i}, 'data') || isempty(bcs{i}.data)
+            continue
+        end
+
+        if ~isa(bcs{i}.data, 'function_handle')
+            error('bcs{%d}.data should be a function of time or a function of time and space',i);
+        end
+
+        b = diffOp.grid.getBoundary(bcs{i}.boundary);
+
+        dim = size(b,2);
+
+        if nargin(bcs{i}.data) == 1
+            % Grid data (only function of time)
+            assertSize(bcs{i}.data(0), 1, size(b));
+        elseif nargin(bcs{i}.data) ~= 1+dim
+           error('sbplib:scheme:bcSetup:DataWrongNumberOfArguments', 'bcs{%d}.data has the wrong number of input arguments. Must be either only time or time and space.', i);
+        end
+    end
+end
+
+function [ok, isSym, dataStruct] = parseData(bc, penalty, grid)
+    if ~isfield(bc,'data') || isempty(bc.data)
+        ok = false;
+        return
+    end
+    ok = true;
+
+    nArg = nargin(bc.data);
+
+    if nArg > 1
+        % Symbolic data
+        isSym = true;
+        coord = grid.getBoundary(bc.boundary);
+        dataStruct.penalty = penalty;
+        dataStruct.func = bc.data;
+        dataStruct.coords = num2cell(coord, 1);
+    else
+        % Grid data
+        isSym = false;
+        dataStruct.penalty = penalty;
+        dataStruct.func = bcs{i}.data;
+    end
+end