Editing Column Properties


You can control the details of how columns are handled and displayed by tapping the arrow button to the right of the column name in either the Layout tab or the Column tab.








Column Properties


Note that when you change the properties of a field from the Columns tab, any encoding that is derived from that column will inherit the properties that you customize. Conversely, when you customize a column that has been added to the Layout tab, the original column will remain unchanged. If you subsequently add the same column to another encoding, or delete and then re-add the column to an encoding, you will lose any customizations you have assigned to the column.


The Properties tab of the column configuration view allow you to specify the following customizations:

Caption: This is the title of the column that will appear in the Glimpse user interface. It defaults to the name of the column that originally appeared in the imported spreadsheet.

Variable Type: Either continuous or discrete. By default, when importing columns from the spreadsheet, any field that Glimpse identifies as a number will be assigned the continuous variable type, and all other columns will be treated as discrete. You can override this behavior to change how Glimpse behaves when the column is added to an encoding. One common case where you may need to customize a column’s variable type is when the spreadsheet column represents a year. Since years are numbers, Glimpse will assume that the column should be an aggregate continuous column, but more commonly you will want to treat a year as a discrete type, like other date types.

Column Type: this is the underlying column type that Glimpse has assigned to the column. This can sometimes be changed.

Mark Type: This is the default type of the mark that will be assigned to a visualization when the column is first selected.

Aggregation: This is the aggregation that will be assigned to continuous fields. By default, Glimpse always chooses the Sum aggregate, but you can change this to Average, Min, Max, or Count. The type of aggregation defines how multiple continuous values are aggregated and summarized together in your visualization, which makes this one of the most important field types to customize.

Calendar Unit: This is the date type that will be used for discrete fields. By default, this is set to Year, meaning that date fields will be grouped together by the Year, but other common values you may want to specify are Quarter, Month, and Weekday.





Column Formatting

The Formatting tab of the column configuration view allows you to control the formatting parameters of column text. The formatting section has separate sections for the Title & Header format (which controls how field titles are displayed when they are displayed in the header areas), and the Field Mark Value format (which controls how the values are displayed on the canvas).