groupedBar

// Make a plot with three groups:  One for "In Meeting", one for "On Phone",
// and one for "Coding".  The plot will also have two bar colors:  One for
// "Without Caffeine" and one for "With Caffeine".
auto withoutCaffeine = [8, 6, 3];
auto withCaffeine = [5, 3, 1];
auto sleepinessPlot = groupedBar(
    iota(3), [withoutCaffeine, withCaffeine], 0.6,
    ["W/o Caffeine", "W/ Caffeine"],
    [getColor(64, 64, 255), getColor(255, 64, 64)]
);
auto sleepinessFig = Figure(sleepinessPlot)
    .title("Sleepiness Survey")
    .yLabel("Sleepiness Rating")
    .xLabel("Activity")
    .legendLocation(LegendLocation.right)
    .horizontalGrid(true)
    .xTickLabels(
        iota(3),
        ["In Meeting", "On Phone", "Coding"]
    );