Histograms Bar Chart and Legend

Histograms, Bar Chart, and Legend

Around the Main Summary View Heatmap sit three supporting views. Each is interactive, and each is linked to the heatmap — acting in one highlights the matching records (in orange) across the panel and updates the export counter. This page documents all of their interactions.

For the overall selection model and how to export, see Selecting and Exporting Data.

Framing histograms

Two histograms frame the heatmap and show how records are distributed along each axis:

• Bottom histogram (x-axis distribution): one bar per x-bin, height = record count. Drawn for continuous/datetime x-axes. (For a categorical/list x-axis, the space below the heatmap carries count/sharedness strips instead — see Main Summary View Heatmap.)
• Right histogram (y-axis distribution): one bar per y-bin, width = record count. Uses a log scale when the counts span a wide range.

Interactions

View	Action	Effect
Bottom histogram	Drag horizontally	Brushes a range on the x-axis. The matching heatmap cells highlight orange and the export counter updates.
Right histogram	Drag vertically	Brushes a range on the y-axis, highlighting the matching cells.
Either	Release with no selection	Clears that brush.

The histogram brushes and the heatmap's 2D-brush mode are the same "box" selection stream, so they stay in sync — brushing the histograms moves the heatmap box and vice versa. A brush set elsewhere (e.g. a category filter or the 2D-brush) is reflected back onto the histograms automatically.

Categorical bar chart

The bar chart (lower area of the panel) shows the top 10 values of the categorical column by frequency, as a filter control. Its title names the variable; a log scale kicks in when counts span a wide range.

Interactions

Action	Effect
Hover a bar	The bar darkens and the whole panel filters to records with that category — the heatmap, histograms, and legend all update live.
Click a bar	Pins the filter so it persists after the mouse leaves. Click again to unpin.
Mouse leaves (unpinned)	The bar returns to its normal color and the filter reverts to only the pinned categories (or no filter if none are pinned).

Pinned categories are always part of the filter, even while you hover other bars, so you can build up a multi-category filter.

Empty state

When there is no categorical variable configured (or the synthetic "no grouping" column is in that role), the chart shows a centered two-line note: "Categorical: n/a" / "No categorical variable." See Configuration for how the synthetic column appears as n/a.

Color legend

The legend sits to the side of the heatmap and shows the color scale for the cells — a vertical gradient labeled with the color variable and its aggregation, e.g. nodes_requested (avg). It serves two purposes: a key for reading cell colors, and a third selection control.

Interactions

Action	Effect
Drag vertically on the gradient	Brushes a range of color values. Every cell whose aggregated color falls in that range is selected — regardless of its x/y position — and highlighted orange. This is the "color band" selection stream.
Release with no selection	Clears the color brush.

A brushed color range is reflected onto the legend when set from elsewhere, and survives re-renders triggered by other selections.

Export counter

The legend header shows a live count: "No. of Records Selected for Export: N." It reflects the union of all selection streams in the panel (box brush + pins + color band) and briefly flashes orange whenever the selection changes, as feedback that your export set updated.

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Next: Selecting and Exporting Data · Main Summary View Heatmap · API Reference