Performing a line similarity comparison

The Line Similarity tool is used to compare the lines in a line chart to a selected master line.

About this task

Before you begin

The Line similarity tool cannot be used unless you have created a suitable line chart to base the calculation on. For example, to perform a line similarity comparison. Performing a line similarity clustering can only be done in the installed client.

About this task

You cannot use multiple Y-axes scales.
You cannot use an X-axis which is both continuous and binned.
All lines in the line chart must have the same starting points on the X-axis, and the same end points.

See below for more information about how to set up the line chart.

Procedure

Create a line chart visualization by clicking Visualization types on the authoring bar, and then, in the Visualization types flyout, selecting Line chart.
The tool uses the lines specified in a line chart to define the data for the calculation.
Make sure that all values that should be included in the calculation are selected on the Y-axis.
If more than one column is selected on the Y-axis, make sure that (Column Names) is selected on the X-axis.
(Column Names) is an option that treats the names of the columns selected on the Y-axis as separate categories.
Use Line by, Color by or Trellis by to split the lines according to at least one column, to create multiple lines.

Tip: See examples on how to split lines under Creating a line chart. If you want to create one line for each individual row, one of these options must be set to define a unique identifier for all rows. (Row Number) is a fictive column representing the row index of all rows and can be used for this purpose.
On the menu bar, select Tools > Line similarity.

Tip: You can also right-click the line chart, and select Line similarity from the pop-up menu.
Make sure that the line chart you just created is selected under Line chart to work on.
Select whether to Create new result column or Update existing result column.
Update existing is only available when you have previously performed a line similarity comparison during this analysis.
Select a Distance measure to use in the calculation.
For more information see Correlation or Euclidean distance.
Select whether to use a master line Based on marked lines or on a Custom shape.
The marked lines are used to create a master line which is the average of all marked lines. With the custom alternative, you can select a master line from a number of predefined line shapes.
Note: If the currently marked lines contain empty values, then they cannot be used to create a master line, and the custom alternative will automatically be selected.
Click OK.
Two new columns are added to the data table (and two new filters representing the columns are shown in the data and filters panels).
Note: The result columns are based on a snapshot of the line chart from the moment of performing the calculation and they might become invalid when any additional filtering is applied.