chart-items-limit

Arguments: chart-widget

Returns the value of the chart-items-limit property of a chart-widget. The value may be set at creation time by passing the :chart-items-limit initarg, or any time later by calling (setf chart-items-limit).

chart-items-limit is the maximum number of chart items that a chart-widget will collect. The value should be a positive integer, or else nil for no limit. The default value is nil.

If set-chart-value is called with an item index that would cause the number of chart items to exceed this limit, then older chart items are first removed to avoid exceeding the limit when the new item is added. ("Older" chart items means items with the lowest indices.)

This property would typically be used when collecting data incrementally over time, to cause a chart-widget to display the most recent N pieces of data while throwing away older data for efficiency.

To temporarily exclude older items from view rather than permanently removing them, use chart-items-min-index.

See also chart-items-pushed-off.

See chart-widget and also cg-chart-widget.htm.

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This page was not revised from the 10.0 page.
Created 2019.8.20.