fix(matlab): rate 0.02 grid, batch 3

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

analysis/matlab/variations/naive_boxa_d6_13/plotcurve.m

@@ -54,12 +54,20 @@ if strcmp(metric, 'count')       % count: tick every 5, but label only every 10
         if mod(yt(k), 10) == 0; lbl{k} = num2str(yt(k)); else; lbl{k} = ''; end
     end
     set(gca, 'YTick', yt, 'YTickLabel', lbl);
-else                             % rate: fine minor tick marks every 0.02 (no labels)
+else                             % rate: tick every 0.02, label only every 0.1
     yl = ylim(gca);
-    set(gca, 'YMinorTick', 'on');
-    ax = gca; ax.YAxis.MinorTickValues = 0 : 0.02 : ceil(yl(2) / 0.02) * 0.02;
+    yt = 0 : 0.02 : ceil(yl(2) / 0.02) * 0.02;
+    lbl = cell(1, numel(yt));
+    for k = 1:numel(yt)
+        if abs(yt(k) / 0.1 - round(yt(k) / 0.1)) < 1e-9   % multiple of 0.1
+            lbl{k} = num2str(round(yt(k), 1));
+        else
+            lbl{k} = '';
+        end
+    end
+    set(gca, 'YTick', yt, 'YTickLabel', lbl);
 end
-grid on
+grid on                          % gridlines fall on the ticks (rate: every 0.02)
 % Add breathing room between the y-axis label and the tick numbers.
 set(ylh, 'Units', 'normalized');
 yp = get(ylh, 'Position');