Documentation Vision Library+ Documentation

Event Analytics Pie+

Event Analytics Pie+ turns event frames into a pie or donut chart. Count events or total a number such as lost production for each category, draw one pie per production line, and let readers click a slice to drill down or filter the rest of the display.

Overview

Pie chart of production loss by root cause with a legend

Watch the demo

See Event Analytics Pie+ in a practical PI Vision workflow.

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When to use it

Use Event Analytics Pie+ when you need to:

  • Show what share of the events each category makes up, such as planned and unplanned downtime.
  • Show what share of a total each cause contributes, such as production loss by root cause.
  • Keep the largest slices and group the rest as Others.
  • Draw one pie for each value of a second attribute, such as one pie for each production line.
  • Let readers click a slice to see its sub-categories or to filter other symbols.

Choose Event Analytics Chart+ when readers must compare precise values or follow a total over time. Choose Event Analytics Pivot+ for two categories in a grid of numbers, and Pie Chart+ to show shares of PI Points or attributes that are not event frames.

Before you begin

  • Prepare an event frame template that has events in the time range you will display.
  • To total or average a number, the event frames need a numeric attribute. Text attributes can only be counted.
  • For click actions that change other symbols, add other symbols that listen to filters, such as Event Filter+ or another analytics symbol. See Filtering dashboards.

Add and set up the symbol

  1. Select Event Analytics Pie+ in the PI Vision symbol gallery.
  2. Drag an event frame attribute from the Event Frame Search results onto the display. The pie starts empty.
  3. Right-click the symbol, select Search Criteria..., choose the database and event frame template, and select Apply.
  4. Right-click the symbol and select Configure Event Analytics Pie.... Under Dimension, open Values. Set Value (1) to the attribute you want to count, for example |Classification, and Summary (2) to Count.
  5. Open Arguments and set Value (3) to the same attribute.
Values and Arguments groups with Value and Summary marked

The pie shows one slice for each value of the attribute, sized by the number of events. Here planned downtime is 8 events and unplanned downtime is 38 events. The title is the Title of the value.

Pie chart counting downtime events by classification

Note: Attribute names show a leading |. Hierarchical attributes such as |Root Cause|Level1 give one entry per level, and |Root Cause gives the full path, for example Equipment breakdown|Electrical.

Common tasks

Total a number for each cause

Use this when slices should show how much, not how many, for example the production loss caused by each root cause.

  1. In the configuration pane, open Values.
  2. Set Value (1) to a numeric attribute, such as |Loss.
  3. Set Summary (2) to Sum. Average, Min, Max, Median, and Standard Deviation are also available.
  4. Optionally enter a Title (3) for the pie.
  5. Open Arguments and set Value (4) to the attribute that defines the slices, such as |Root Cause|Level1.
Values group with Sum of Loss and Arguments group with Root Cause Level1

Each slice is the total for one cause, and its label shows the value with its unit.

Pie chart of total production loss by root cause

Keep the largest slices and group the rest

Use this when an attribute has more values than the pie can show.

  1. In the configuration pane, open Arguments and select the argument.
  2. Set Top N (1) to ON and Mode (2) to Top. Bottom keeps the smallest slices.
  3. Enter the Count (3), for example 5.
  4. Set Value (4) to the value that decides the ranking.
  5. Set Others (5) to ON to add one slice that sums everything else.
Arguments group with Top N on, a count of 5, and Others on

The pie keeps the five largest slices and adds an Others slice.

Pie chart with five root causes and an Others slice

Draw one pie for each production line

Use this when you want the same breakdown for several assets or categories side by side.

  1. In the configuration pane, open Series and select +.
  2. Set Value (1) to the attribute that splits the pies, such as |Production Line.
  3. Optionally enter a Caption (2). Top N (3) keeps only the top or bottom pies.
Series group with Value set to Production Line
  1. Open Style. Under Layout (1), select Auto, Rows, or Columns. With Rows or Columns, set the Count (2).
Style group with Layout set to Columns and a count of 3

The symbol draws one pie for each production line, titled with the line name, and arranges them in the grid you chose. The legend lists the slice categories once for all pies.

Six pies of production loss by root cause, one for each production line

Show shares as a donut with percentages

Use this when readers care about proportion more than the raw values.

  1. In the configuration pane, open Style.
  2. Under Type, select the donut button (1).
Type buttons with the donut selected
  1. Open Data Labels. Set Name (1) and Value (2) to OFF.
  2. Set Percent (3) to ON.
Data Labels group with Name and Value off and Percent on

Each slice shows its share of the pie. Position places the labels inside, outside, or automatically. The legend still names the slices.

Donut chart with a percentage on each slice

Let readers drill down or filter with a click

Use this when a click on a slice should show what is behind it, or change the other symbols on the display.

  1. For a drill-down, open Arguments in the configuration pane and add the attributes from the top level to the bottom level, for example |Root Cause|Level1 and then |Root Cause|Level2.
  2. Under Interactivity, open Selection and set Click Action (1) to Drilldown or Filter.
  3. For Drilldown, set Drilldown (2) to Argument to drill through the arguments, or to Series to drill through the series.
Selection group with Click Action set to Drilldown

With Drilldown, a click on a slice replaces the pie with the next level for that slice, and a button at the top moves back up one level. A slice named No Data stands for events that have no value at that level.

Pie chart showing the sub-causes of Equipment breakdown
  1. For Filter, open Filtering and set Output Mode (2) to Master to filter every symbol that listens to Master filters. Linked and Both publish to named channels. See Filtering dashboards.
Selection and Filtering groups with Click Action set to Filter and Output Mode set to Master

With Filter, a click on a slice makes the other symbols recalculate for the events of that category and show a filter icon at their top right. The pie that you clicked keeps all its slices and shows a button to clear the filter. In the picture, a click on Operator error leaves 5 downtime events on the left pie.

Display where the classification pie follows the clicked root cause

Check the numbers behind a slice

Use this when a reader asks which events make up a slice, or needs the numbers in a spreadsheet.

  1. Hover the pie and select Inspect Data in its toolbar at the top right.
  2. In the Summary tab, select a row (2), for example Maintenance. The tab has one row for each slice: the pie, the category, the value, and its percentage of the pie.
  3. Select the Rows tab. It lists the events behind that slice with their properties and attributes.
  4. To keep the data, select CSV, JSON, or XLSX (4). The file holds the tab you are viewing.
Inspect Data dialog with the Maintenance slice selected

The count (1) shows how many rows the tab holds, and Data as of (3) when the dialog read the pie. Select Refresh to read it again. Select the same Summary row again to see all events.

Use the symbol

Pie chart with numbered callouts
What it shows
(1)The title of the pie. With a series, each pie has its own title.
(2)A slice. Its angle is the share of the count or total for that category.
(3)A data label with the name, value, or percentage, as configured.
(4)The legend. One entry per slice category, with the slice color.
Tooltip over the Equipment breakdown slice
  • Hover a slice to see its category, value, and percentage of its pie.
  • Click a slice to do what Click Action says: nothing, drill down, or publish a filter. A click never writes to the PI System.
  • Toolbar: hover the pie to show its buttons at the top right. Inspect Data shows the numbers and the events behind the pie, see Check the numbers behind a slice. Clear Filter shows while a click on this pie filters the display or has drilled down, and clears that filter or drill-down. Fullscreen opens the pie at the size of the display, where a click acts as on the embedded chart. Download offers PNG, SVG, and PDF images and CSV, JSON, and XLSX data with one row for each slice. Your administrator can hide the data formats and the export buttons of Inspect Data.
  • Time range: the pie follows the display time range. With a Time Bar, the symbol has its own range.
  • Filters: an Event Filter+ or another Master filter narrows the events and a filter icon appears. Ignore Master keeps the pie unaffected.
  • No events: the pie is empty. Change the display time range or the search criteria.

Configure the symbol

Right-click the symbol and select Configure Event Analytics Pie.... The right-click menu also offers Search Criteria.... The groups appear in this order.

Dimension

GroupSettingWhat it does
ValuesValueThe attribute to summarize. The pie uses the first value in the list. Event properties include Duration (the whole event frame), Duration in Range (only the part inside the symbol's time range; use Sum for the time within the shown period), and Duration in Range, Overlaps Merged (the same, but time already covered by an earlier event frame on the same asset counts once; use it when event frames on one asset can overlap).
SummaryCount, Count Distinct, Sum, Min, Max, Average, Median, or Standard Deviation for numbers. Text attributes offer only Count and Count Distinct. Used in Total a number for each cause.
Title, ShowTitle names the value and is shown as the pie title. Show set to OFF hides the value but keeps it for ranking.
ArgumentsValueThe attribute that defines the slices. Several arguments combine into one category, or become drill-down levels.
Group IntervalAvailable for time attributes. Groups by Day-Month-Year, Month-Year, Year, and other intervals.
TitleNames the argument.
Top NKeeps the top or bottom slices. Mode, Count, Value, and Others set the details. Used in Keep the largest slices and group the rest.
SeriesValue, Group Interval, CaptionSplit the data into one pie for each value. Used in Draw one pie for each production line.
Top NKeeps the top or bottom pies. Others adds one pie that combines the rest.

Trend Options

GroupWhat it does
TitleShows a title and a sub title, with font size and alignment. Show Pie Titles puts a title above each pie when a series is used.
StyleTheme, Surface, Container Style, and Font Size. Type selects the pie or the donut. Layout arranges several pies: Auto fits them to the symbol, Rows and Columns fix the number of rows or columns. Used in Show shares as a donut with percentages and Draw one pie for each production line.
LegendEnabled, Position, Placement (outside or inside the chart), Alignment, Size, and whether the Color shows as a Marker or as Text. The legend always lists the slice categories.
Data LabelsShow, Position (Auto, Outside, Inside), Name, Value, Percent, Background, and Font Size.
TooltipShow turns the hover tooltip on or off.
ToolbarShow Toolbar turns the toolbar with Inspect Data, Clear Filter, Fullscreen, and Download on or off. On by default. Reveal shows it On Hover or keeps it in view Always.
ColoringAuto uses the theme palette. Custom lists every slice category and lets you pick its color.

Interactivity

SettingWhat it does
Click ActionNone, Drilldown, or Filter. Used in Let readers drill down or filter with a click.
DrilldownAvailable when Click Action is Drilldown. Drills through the Argument or Series list.
Filter IndicatorCompact shows a filter icon, Full adds the event count, and Hidden shows nothing.
Ignore MasterON ignores Master filters on the display. Linked inputs still apply.
Linked InputsMaps a named channel from a publisher to a property of the events. See Filtering dashboards.
Output ModeAvailable when Click Action is Filter. Master, Linked, or Both.

Attributes, Time Bar, and Numbers

SettingWhat it does
AttributesThe event frame attributes the symbol can use in Value lists. Drag more attributes onto the symbol to add them.
Time BarGives the symbol its own range with the shared Time Bar. Available when the search uses a time bar range.
NumbersThe number format for values and labels.

Troubleshooting and limitations

SymptomCauseWhat to do
The pie is empty.No events match the search in the display time range, or no value or argument is set.Open Search Criteria... and widen the search, change the display time range, and check Values and Arguments.
A new symbol does not use the search you ran.The symbol keeps its own search criteria.Right-click the symbol, select Search Criteria..., and select Apply.
Clicking a slice does nothing.Click Action is None, or the drill-down is at the last level.Set Click Action under Interactivity > Selection. A drill-down needs a second argument or series.
Slice labels are cut off or overlap.The symbol is small for the number of slices.Enlarge the symbol, turn off Name in Data Labels and use the legend, or use Top N.
Sum and Average are not offered.The attribute is text.Choose a numeric attribute. Text attributes offer Count and Count Distinct.
Fewer events than expected.A filter from another symbol is active.Clear the filter, or set Ignore Master to ON.

Limitation: The pie draws only the first value. It has no total in the center.

Limitation: Slice colors do not follow limits. Use Coloring > Custom to give a category a fixed color.

Limitation: The pie publishes one selected slice at a time. It cannot publish several slices.

Limitation: A filter matches the exact category. Selecting Equipment breakdown does not include Equipment breakdown|Electrical in a pie that uses |Root Cause.