--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/+multiblock/+domain/Rectangle.m	Fri Sep 07 14:40:58 2018 +0200
@@ -0,0 +1,188 @@
+classdef Rectangle < multiblock.Definition
+    properties
+
+    blockTi % Transfinite interpolation objects used for plotting
+    xlims
+    ylims
+    blockNames % Cell array of block labels
+    nBlocks
+    connections % Cell array specifying connections between blocks
+    boundaryGroups % Structure of boundaryGroups
+
+    end
+
+
+    methods
+        % Creates a divided rectangle
+        % x and y are vectors of boundary and interface positions.
+        % blockNames: cell array of labels. The id is default.
+        function obj = Rectangle(x,y,blockNames)
+            default_arg('blockNames',[]);
+
+            n = length(y)-1; % number of blocks in the y direction.
+            m = length(x)-1; % number of blocks in the x direction.
+            N = n*m; % number of blocks
+
+            if ~issorted(x)
+                error('The elements of x seem to be in the wrong order');
+            end
+            if ~issorted(flip(y))
+                error('The elements of y seem to be in the wrong order');
+            end
+
+            % Dimensions of blocks and number of points
+            blockTi = cell(N,1);
+            xlims = cell(N,1);
+            ylims = cell(N,1);
+            for i = 1:n
+                for j = 1:m
+                    p1 = [x(j), y(i+1)];
+                    p2 = [x(j+1), y(i)];
+                    I = flat_index(m,j,i);
+                    blockTi{I} = parametrization.Ti.rectangle(p1,p2);
+                    xlims{I} = {x(j), x(j+1)};
+                    ylims{I} = {y(i+1), y(i)};
+                end
+            end
+
+            % Interface couplings
+            conn = cell(N,N);
+            for i = 1:n
+                for j = 1:m
+                    I = flat_index(m,j,i);
+                    if i < n
+                        J = flat_index(m,j,i+1);
+                        conn{I,J} = {'s','n'};
+                    end
+
+                    if j < m
+                        J = flat_index(m,j+1,i);
+                        conn{I,J} = {'e','w'};
+                    end
+                end
+            end
+
+            % Block names (id number as default)
+            if isempty(blockNames)
+                obj.blockNames = cell(1, N);
+                for i = 1:N
+                    obj.blockNames{i} = sprintf('%d', i);
+                end
+            else
+                assert(length(blockNames) == N);
+                obj.blockNames = blockNames;
+            end
+            nBlocks = N;
+
+            % Boundary groups
+            boundaryGroups = struct();
+            nx = m;
+            ny = n;
+            E = cell(1,ny);
+            W = cell(1,ny);
+            S = cell(1,nx);
+            N = cell(1,nx);
+            for i = 1:ny
+                E_id = flat_index(m,nx,i);
+                W_id = flat_index(m,1,i);
+                E{i} = {E_id,'e'};
+                W{i} = {W_id,'w'};
+            end
+            for j = 1:nx
+                S_id = flat_index(m,j,ny);
+                N_id = flat_index(m,j,1);
+                S{j} = {S_id,'s'};
+                N{j} = {N_id,'n'};
+            end  
+            boundaryGroups.E = multiblock.BoundaryGroup(E);
+            boundaryGroups.W = multiblock.BoundaryGroup(W);
+            boundaryGroups.S = multiblock.BoundaryGroup(S);
+            boundaryGroups.N = multiblock.BoundaryGroup(N);
+            boundaryGroups.all = multiblock.BoundaryGroup([E,W,S,N]);
+            boundaryGroups.WS = multiblock.BoundaryGroup([W,S]);
+            boundaryGroups.WN = multiblock.BoundaryGroup([W,N]);
+            boundaryGroups.ES = multiblock.BoundaryGroup([E,S]);
+            boundaryGroups.EN = multiblock.BoundaryGroup([E,N]);
+
+            obj.connections = conn;
+            obj.nBlocks = nBlocks;
+            obj.boundaryGroups = boundaryGroups;
+            obj.blockTi = blockTi;
+            obj.xlims = xlims;
+            obj.ylims = ylims;
+
+        end
+
+
+        % Returns a multiblock.Grid given some parameters
+        % ms: cell array of [mx, my] vectors
+        % For same [mx, my] in every block, just input one vector.
+        function g = getGrid(obj, ms, varargin)
+
+            default_arg('ms',[21,21])
+
+            % Extend ms if input is a single vector
+            if (numel(ms) == 2) && ~iscell(ms)
+                m = ms;
+                ms = cell(1,obj.nBlocks);
+                for i = 1:obj.nBlocks
+                    ms{i} = m;
+                end
+            end
+
+            grids = cell(1, obj.nBlocks);
+            for i = 1:obj.nBlocks
+                grids{i} = grid.equidistant(ms{i}, obj.xlims{i}, obj.ylims{i});
+            end
+
+            g = multiblock.Grid(grids, obj.connections, obj.boundaryGroups);
+        end
+
+        % label is the type of label used for plotting,
+        % default is block name, 'id' show the index for each block.
+        function show(obj, label, gridLines, varargin)
+            default_arg('label', 'name')
+            default_arg('gridLines', false);
+
+            if isempty('label') && ~gridLines
+                for i = 1:obj.nBlocks
+                    obj.blockTi{i}.show(2,2);
+                end
+                axis equal
+                return
+            end
+
+            if gridLines
+                m = 10;
+                for i = 1:obj.nBlocks
+                    obj.blockTi{i}.show(m,m);
+                end
+            end
+
+
+            switch label
+                case 'name'
+                    labels = obj.blockNames;
+                case 'id'
+                    labels = {};
+                    for i = 1:obj.nBlocks
+                        labels{i} = num2str(i);
+                    end
+                otherwise
+                    axis equal
+                    return
+            end
+
+            for i = 1:obj.nBlocks
+                parametrization.Ti.label(obj.blockTi{i}, labels{i});
+            end
+
+            axis equal
+        end
+
+        % Returns the grid size of each block in a cell array
+        % The input parameters are determined by the subclass
+        function ms = getGridSizes(obj, varargin)
+        end
+    end
+end