Diff mode

Compare two datasets directly — hueglint renders the delta between them on a diverging color scale, instead of you building two separate charts and eyeballing the difference.

chart.loadDiff(thisWeekData, lastWeekData, { valueLabel: 'Requests' });

The diverging scale is purple-to-orange, not red-to-green — a deliberate choice, since red-green is the exact color pair that’s unreadable for the most common form of color vision deficiency. Tooltips in diff mode show the actual before-and-after values, not just the delta, so you always have the real numbers to hand.

Diff mode requires the two datasets to share at least some matching (row, col) pairs. Mismatched cells are skipped with a console warning rather than silently dropped without explanation — a completely empty overlap throws a clear error instead of rendering nothing.