Details on Limit Data Using Expression


You can limit what data should be available for a certain visualization using an expression. This way, you can set a "hard filter" on a visualization to make sure that certain values are never included in the calculations behind the visualization, regardless of any filtering in the Filters panel. For example, you can make sure that one visualization only shows data for a certain state by adding the expression similar to [State]="Nevada". See also Limiting What is Shown in Visualizations.

  1. Click on the visualization for which you want to limit the data using an expression to make it active.

  2. Select Edit > Visualization Properties.

  3. Go to the Data page.

  4. At the bottom of the page, next to Limit data using expression, click on Edit....

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Option

Description

Available columns

Shows all columns that you can use in the calculation of a new column.

Select a column by clicking on it in the list and then click on the Insert Columns button, or double-click on the column to send it to the Expression field. Press Ctrl or Shift to select multiple columns.

You can narrow down the list of available columns by typing a part of a name in the "Type to search" field. You can also enter an expression in the field using the rules described on the Searching in TIBCO Spotfire page.

Insert Columns

Inserts the columns selected in the Available columns list at the current cursor position in the Expression field.

Available properties for column

Shows all properties that you can use in the calculation of a new column. You can narrow down the list of available properties by using the search field. The column properties shown are specific to the column selected in the Available columns list to the left.

Select a property by clicking on it in the list and then click on the Insert Properties button; or double-click on the property to send it to the Expression field. The property will automatically be inserted as text. However, there may be occasions where you need to insert the property as a function to receive the desired result. See Properties in Expressions for more information. Use the pop-up menu in this field to select how to insert the property or type the correct syntax manually.

If you want to define a new property to use in the expression, right-click in the Available properties field and select New > [Property Type] Property... from the pop-up menu. You can also edit or delete custom properties by using the pop-up menu.

Insert Properties

Inserts the properties selected in the Available properties for column list at the current cursor position in the Expression field.

Category

Select a category of functions to limit the choices in the Function list:

All functions

Binning functions

Conversion functions

Date and Time functions

Logical functions

Math functions

Operators

Property functions

Ranking functions

Spatial functions

Statistical functions

Text functions

Function

Select a function by clicking on it in the list and then click on the Insert Function button, or double-click on the function to send it to the Expression field.

Type a search string in the text field to limit the number of items in the Functions list.

You can also click on any function and type the first letter of the desired function name to jump to a specific location in the list.

Description

Shows a brief description of the selected function. For more detailed descriptions, see the Expression Language chapter.

Insert Function

Inserts the selected function at the current cursor position in the Expression field.

Expression

This is the text field in which you build your expression. You can insert columns and functions from the lists, or enter text as in any standard text editor. In this context, the expression must be of type "Boolean", since it will be used as a filter.

See Expression and Script Editor Keyboard Shortcuts for information about available shortcuts.

Clear the expression field and click OK to remove a previously added expression filter.

Recent expressions

Displays the ten expressions you have most recently created. You can select one of these and click the Insert button to insert the expression into the Expression field.

Insert

Inserts the selected Recent expression into the Expression field. This will replace the entire content of the Expression field.

Resulting expression

Of interest when preprocessor functions (such as ${PropertyName}) are used in the expression only. Displays the expression after all occurrences of the property have been replaced with its current value or values.

See also:

General Syntax

Functions Overview

Properties in Expressions