bug fix

Rather obscure error that occurred only with MixedModels and when the
point estimate was ‘mode’

Added a regression test to test_Stochastic.m

ddToolbox/Variables/Stochastic.m

@@ -205,8 +205,8 @@ function panOptions(obj)
 
 		function obj = calculateModeAndDensity(obj)
 			if any(isnan(obj.samples))
-				obj.mode = [];
-				obj.density = [];
+				obj.mode = NaN;
+				obj.density = NaN;
 			else
 				obj.xi = linspace( min(obj.samples(:)), max(obj.samples(:)), 1000);
 				obj.xi = [obj.xi(1) obj.xi obj.xi(end)]; % fix to avoid plotting artifacts

tests/test_Stochastic.m

@@ -0,0 +1,19 @@
+classdef test_Stochastic < matlab.unittest.TestCase
+
+	properties
+	end
+
+	methods (Test, TestTags = {'Unit'})
+
+		function check_mode_is_NaN_when_NaN_samples_provided(testCase)
+			% when we provide NaN as samples to a Stochastic object, check
+			% we set obj.mode as NaN
+			univariateObject = Stochastic('testVariable');
+			samples = NaN;
+			univariateObject.addSamples(samples);
+
+			testCase.verifyEqual( univariateObject.mode, NaN )
+		end
+
+	end
+end