reporting: add subtitles for graphs, closes #580

doc/dynare.texi

@@ -10769,8 +10769,14 @@ The color to use in the shaded portion of the graph. Default:
 @item shadeOpacity, @code{DOUBLE}
 The opacity of the shaded area, must be in @math{[0,100]}. Default: @code{20}
 
-@item title, @code{STRING}
-Title for the graph. Default: @code{none}
+@anchor{graph.title}
+@item title, @code{STRING} | @code{CELL_ARRAY_STRINGS}
+Same as @ref{title}, just for graphs.
+
+@item titleFormat, @code{STRING}
+The format to use for @ref{graph.title,,the graph title}. Unlike
+@ref{titleFormat}, due to a constraint of TikZ, this format applies to
+the title and subtitles. Default: @code{TikZ default}
 
 @item width, @code{DOUBLE}
 The width of the graph, in inches. Default: @code{6.0}

matlab/reports/@graph/graph.m

@@ -36,6 +36,7 @@ o = struct;
 o.series = {};
 
 o.title = '';
+o.titleFormat = '';
 o.ylabel = '';
 o.xlabel = '';
 
@@ -97,7 +98,11 @@ elseif nargin > 1
 end
 
 % Check options provided by user
-assert(ischar(o.title), '@graph.graph: title must be a string');
+if ischar(o.title)
+    o.title = {o.title};
+end
+assert(iscellstr(o.title), '@graph.graph: title must be a cell array of string(s)');
+assert(ischar(o.titleFormat), '@graph.graph: titleFormat file must be a string');
 assert(ischar(o.xlabel), '@graph.graph: xlabel file must be a string');
 assert(ischar(o.ylabel), '@graph.graph: ylabel file must be a string');
 assert(ischar(o.figname), '@graph.graph: figname must be a string');

matlab/reports/@graph/writeGraphFile.m

@@ -88,8 +88,20 @@ fprintf(fid, ['},\n',...
               'axis lines=box,\n'...
               'unbounded coords=jump,\n'], o.width, o.height);
 
-if ~isempty(o.title)
-    fprintf(fid, 'title=%s,\n', o.title);
+if ~isempty(o.title{1})
+    fprintf(fid, 'title style={align=center');
+    if ~isempty(o.titleFormat)
+        fprintf(fid, ',font=%s', o.titleFormat);
+    end
+    fprintf(fid, '},\ntitle=');
+    nt = length(o.title);
+    for i=1:nt
+        fprintf(fid, '%s', o.title{i});
+        if i ~= nt
+            fprintf(fid, '\\\\');
+        end
+    end
+    fprintf(fid, ',\n');
 end
 
 if o.xAxisTight

tests/reporting/CountryGraphPage.m

@@ -95,6 +95,7 @@ rep = rep.addSeries('data', dc_q{['PCH_GROWTH_' countryAbbr]}, ...
                     'graphLineWidth', 1.5);
 
 rep = rep.addGraph('title', 'Core Inflation (y/y)', ...
+                   'titleFormat', '\Huge', ...
                    'xrange', prange, ...
                    'shade', srange, ...
                    'showZeroline', true, ...

tests/reporting/runDynareReport.m

@@ -150,7 +150,7 @@ rep = rep.addPage('title', 'Jan1 vs Jan2', ...
                   'titleFormat', '\large\bfseries');
 rep = rep.addSection();
 
-rep = rep.addGraph('title', 'World Real Oil Price Index', ...
+rep = rep.addGraph('title', {'World Real Oil Price Index','SUBTITLE'}, ...
                    'xrange', prange, ...
                    'shade', srange, ...
                    'xTicks', [1,5,10,15,find(srange(1)==prange),length(prange)], ...