[plotting] add code and figure to creta errorbar plots

plotting/code/errorbarplot.m

@@ -0,0 +1,43 @@
+% fake some data
+x_data = 0:2*pi/10:2*pi;
+sym_data = sin(repmat(x_data, 10,1)) * 0.75 + (randn(10, length(x_data)) .* cos(repmat(x_data, 10,1)));
+asym_data = sin(repmat(x_data, 10,1)) * 0.75 + (randn(10, length(x_data)) .* cos(repmat(x_data, 10,1)) + 0.5);
+
+% get some data characteristics
+avg_sym = mean(sym_data, 1);
+err_sym = std(sym_data, [], 1);
+avg_asym = median(asym_data, 1);
+err_upper_asym = prctile(asym_data, 75, 1);
+err_lower_asym = prctile(asym_data, 25, 1);
+
+fig = figure();
+set(fig, 'paperunits', 'centimeters', 'papersize', [15 6.5], ...
+    'paperposition', [0.0 0.0 15, 6.5], 'color', 'white')
+subplot(1,3,1)
+errorbar(x_data, avg_sym, err_sym, 'marker', 'o')
+xlim([-.5, 6.5])
+xlabel('x-data')
+ylabel('y-data')
+box('off')
+
+subplot(1,3,2)
+errorbar(x_data, avg_asym, err_lower_asym, err_upper_asym, 'marker', 'o')
+xlim([-.5, 6.5])
+yticklabels([])
+xlabel('x-data')
+box('off')
+
+subplot(1,3,3)
+hold on
+p = fill(cat(2, x_data, fliplr(x_data)), ...
+    cat(2, avg_sym - err_sym, fliplr(avg_sym + err_sym)), ...
+    'b');
+p.FaceAlpha = 0.125;
+p.EdgeColor = 'w';
+xlim([-.5, 6.5])
+yticklabels([])
+box('off')
+xlabel('x-data')
+plot(x_data, avg_sym, 'b', 'linewidth', 1.)
+
+saveas(fig, '../lecture/images/errorbars', 'pdf')