Data Types

In Visual Analytics, the Data Source fields will take on one of the following data types automatically, even if within the Data Source you connected to there are many other data types allowed:

• Number
• Date and Time
• Date
• String

Each of these data types gets interpreted a different way when used in a Chart or View, so it is important to keep that in mind when dealing with your Data Source. It is possible to convert from one type to another. If Visual Analytics incorrectly represents a date stored as the number of milliseconds since December 31, 1969, you can change it to the data type you need by right-clicking on a field and selecting [Change Data Type]. If you pick a new data type, then click [Default] at the bottom of the list. You're setting the data type for this field so that any time you drag it out of the Data Pane to a deck it keeps that data type.

Discrete and Continuous Fields

Fields are also either Discrete (blue) or Continuous (green).

Discrete data is data that can only take specific values, such as the number of people in a marathon (you can't have a half-person), or makes of cars like Ford, GM, Chrysler. Discrete fields generate headers when they are dropped into Columns or Rows decks.

Continuous data is data that can take any value within a specified range such as the amount of time it took a person to complete a marathon. Continuous fields generate axes when they are dropped into Columns or Rows decks.

You can convert a field from Discrete to Continuous by right-clicking on it and choosing [Convert to Continuous].

As an example, you may wish to use DueDate as a Filter. By default Date and Time data type fields are Discrete. Discrete data appear with a blue background when placed in any of Visual Analytics' decks. When viewing the Filter card for DueDate you get a very long list of each individual time recorded in DueDate. Configuring a filter with many thousands of Date and Time records can be extremely time-consuming.

By converting DueDate to Continuous by right-clicking on it in the Filters deck and selecting [Continuous], you now see an interface for choosing a range of dates. It's much faster to narrow down a range of dates than attempting to select them one by one. The background color of Continuous fields are green when they are placed in any of Visual Analytics' decks.

Data Types and Data Formatting

Visual Analytics automatically sets data formatting based on the Data Types it detects in your Data Source. It's possible to choose different formatting than the defaults it applies automatically by right-clicking on fields you've already put in decks and selecting [Format...]

The resulting dialog allows choosing a variety of options for [Number], [Currency], [Scientific], [Percentage] and [Custom] formats.

Once you choose your format and click [OK], this format will be used in the current view and will also appear in the Axes where needed.

Date and Time data can also take on different formatting than what Visual Analytics automatically assigns. Date Formats can be changed by right-clicking Date/Time fields and choosing [Format...] The list of available formats depends on what date grouping options have already been set for a Date field.

Custom Date Formats can be created by typing in Date and Time Format Characters in the desired pattern. The list of characters displays at the bottom of the date field when [Custom] is selected from the left side of the [Date Format] dialog.