Fix component colorbar tick placement in pop_topoplot

.github/workflows/test.yml

@@ -70,6 +70,15 @@ jobs:
             assert(EEG.nbchan == size(EEG.data, 1));
             assert(EEG.pnts == size(EEG.data, 2));
 
+      - name: Run MATLAB regression tests
+        if: steps.matlab.outputs.available == 'true'
+        uses: matlab-actions/run-command@v2
+        with:
+          command: |
+            cd(getenv('GITHUB_WORKSPACE'));
+            results = runtests('tests');
+            assertSuccess(results);
+
       - name: Skip MATLAB smoke
         if: steps.matlab.outputs.available != 'true'
         run: |

functions/popfunc/pop_topoplot.m

@@ -430,22 +430,24 @@
 
 % Draw colorbar
 if colorbar_switch
+    colorbarLimits = maplimits;
+    if ischar(colorbarLimits)
+        colorbarLimits = get(gca, 'clim');
+    end
     if nbgraph == 1
-        if ~ischar(maplimits)
-            ColorbarHandle = cbar(0,0,[maplimits(1) maplimits(2)]);
-        else
-            ColorbarHandle = cbar(0,0,get(gca, 'clim'));
-        end
+        ColorbarHandle = cbar(0,0,colorbarLimits);
         pos = get(ColorbarHandle,'position');  % move left & shrink to match head size
         set(ColorbarHandle,'position',[pos(1)-.05 pos(2)+0.13 pos(3)*0.7 pos(4)-0.26]);
-    elseif ~ischar(maplimits)
-         cbar('vert',0,[maplimits(1) maplimits(2)]);
-    else cbar('vert',0,get(gca, 'clim'));
+    else
+        ColorbarHandle = cbar('vert',0,colorbarLimits);
     end
-    if ~typeplot    % Draw '+' and '-' instead of numbers for colorbar tick labels
-        tmp = get(gca, 'ytick');
-        set(gca, 'ytickmode', 'manual', 'yticklabelmode', 'manual', 'ytick', [tmp(1) 0 tmp(end)], 'yticklabel', { '-' '0' '+' });
-        try, icadefs; set(gca,'FontSize',AXES_FONTSIZE_L+2); catch, end
+    % Signed component labels require a scale spanning negative and positive values.
+    if ~typeplot && colorbarLimits(1) < 0 && colorbarLimits(2) > 0
+        tickLimits = get(ColorbarHandle, 'ylim');
+        zeroTick = tickLimits(1) - colorbarLimits(1)*diff(tickLimits)/diff(colorbarLimits);
+        set(ColorbarHandle, 'ytickmode', 'manual', 'yticklabelmode', 'manual', ...
+            'ytick', [tickLimits(1) zeroTick tickLimits(2)], 'yticklabel', { '-' '0' '+' });
+        try, icadefs; set(ColorbarHandle,'FontSize',AXES_FONTSIZE_L+2); catch, end
     end
 end
 

tests/test_pop_topoplot_colorbar.m

@@ -0,0 +1,97 @@
+function tests = test_pop_topoplot_colorbar
+tests = functiontests(localfunctions);
+end
+
+function setupOnce(testCase)
+root = fileparts(fileparts(mfilename('fullpath')));
+testCase.applyFixture(matlab.unittest.fixtures.PathFixture(root));
+testCase.applyFixture(matlab.unittest.fixtures.PathFixture(fullfile(root, 'functions'), 'IncludingSubfolders', true));
+testCase.TestData.EEG = pop_loadset('filename', 'eeglab_data_epochs_ica.set', 'filepath', fullfile(root, 'sample_data'));
+end
+
+function setup(testCase)
+testCase.TestData.figures = findall(groot, 'Type', 'figure');
+testCase.TestData.visibility = get(groot, 'DefaultFigureVisible');
+set(groot, 'DefaultFigureVisible', 'off');
+figure('Visible', 'off');
+end
+
+function teardown(testCase)
+delete(setdiff(findall(groot, 'Type', 'figure'), testCase.TestData.figures));
+set(groot, 'DefaultFigureVisible', testCase.TestData.visibility);
+end
+
+function testPositiveLimits(testCase)
+checkScale(testCase, [1 2], 2, false);
+end
+
+function testNegativeLimits(testCase)
+checkScale(testCase, [-2 -1], 2, false);
+end
+
+function testSymmetricLimits(testCase)
+checkScale(testCase, [-2 2], 2, true);
+end
+
+function testAsymmetricLimits(testCase)
+checkScale(testCase, [-1 3], 2, true);
+end
+
+function testZeroLowerEndpoint(testCase)
+checkScale(testCase, [0 2], 2, false);
+end
+
+function testZeroUpperEndpoint(testCase)
+checkScale(testCase, [-2 0], 2, false);
+end
+
+function testMultiplePositiveMaps(testCase)
+checkScale(testCase, [1 2], [1 2], false);
+end
+
+function testMultipleSymmetricMaps(testCase)
+checkScale(testCase, [-2 2], [1 2], true);
+end
+
+function testDefaultLimits(testCase)
+pop_topoplot(testCase.TestData.EEG, 0, 2, 'Component', [], 0);
+bar = findall(gcf, 'Type', 'axes', 'Tag', 'cbar');
+verifyNumElements(testCase, bar, 1);
+verifyTrue(testCase, all(diff(get(bar, 'YTick')) > 0));
+verifyEqual(testCase, cellstr(get(bar, 'YTickLabel')), {'-'; '0'; '+'});
+end
+
+function testZeroComponent(testCase)
+EEG = testCase.TestData.EEG;
+EEG.icawinv(:, 2) = 0;
+pop_topoplot(EEG, 0, 2, 'Zero component', [], 0);
+bar = findall(gcf, 'Type', 'axes', 'Tag', 'cbar');
+verifyNumElements(testCase, bar, 1);
+verifyTrue(testCase, all(diff(get(bar, 'YTick')) > 0));
+end
+
+function testUnrelatedAxesUnchanged(testCase)
+other = axes('YTick', [10 20 30]);
+figure('Visible', 'off');
+checkScale(testCase, [-2 2], 2, true);
+verifyEqual(testCase, get(other, 'YTick'), [10 20 30]);
+end
+
+function checkScale(testCase, limits, components, signed)
+pop_topoplot(testCase.TestData.EEG, 0, components, 'Component', [], 0, 'maplimits', limits);
+bar = findall(gcf, 'Type', 'axes', 'Tag', 'cbar');
+verifyNumElements(testCase, bar, 1);
+ticks = get(bar, 'YTick');
+verifyTrue(testCase, all(isfinite(ticks)) && all(diff(ticks) > 0));
+labels = cellstr(get(bar, 'YTickLabel'));
+if signed
+  verifyEqual(testCase, labels, {'-'; '0'; '+'});
+  range = get(bar, 'YLim');
+  mappedZero = limits(1) + (ticks(2)-range(1))/diff(range)*diff(limits);
+  verifyEqual(testCase, mappedZero, 0, 'AbsTol', 1e-12);
+else
+  values = str2double(labels);
+  verifyTrue(testCase, all(isfinite(values)));
+  verifyEqual(testCase, values([1 end]), limits(:), 'AbsTol', 1e-12);
+end
+end