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Chapter 3 Entering, Editing, and Managing Data 61
Specifying Data Types and Modeling Types
Note: You can select Continuous only if your data type is numeric. If Continuous is grayed on the
menu and you want to make the column continuous, first change its data type in the Column Info
window (access this window by highlighting the column and selecting Cols > Column Info).
Using Short-Integer Format
JMP has the ability to store numeric data in as few as 8 bits (one byte). To implement this, you need to
tell JMP to first make short-integer formats available to you in the Column Info window’s Data Type
drop-down menu. Then you should specify how many bytes you want the integers to hold. When you
use the correct short-integer format for your data, you will not see any difference in how the numbers
display, but they will occupy less disk space and use less memory.
To store numeric data in short-integer format:
1 Select File > Preferences and click the Tables option on the left panel.
2 Click the Allow Short Numeric option.
3 Click OK to return to the data table.
4 Double-click the column name whose values you want to be short-integer. The Column Info
window appears.
5 Click the Data Type drop-down menu, and select 1-byte integer, 2-byte integer, or 4-byte
integer. JMP will now store values as integers in the range corresponding to your selection. For
example, when 1-byte integer is selected, the range of numbers you can enter is from -126 to 127.
When 2-byte integer is selected, the range of numbers you can enter is from -32,766 to 32,767.
When 4-byte integer is selected, the range of numbers you can enter is from -2,147,483,646 to
2,147,483,647.
3Entering Data
Choosing Numeric Formats
When you assign a variable’s data type to be numeric, you can also specify the display format for it to
use. To select the numeric format:
1 Select Cols > Column Info or double-click the area above the name of the column in the data grid.
Or, if you are creating a new column, select Cols > New Column.
2 Click the drop-down menu beside Format, as shown in Figure 3.14, and select the option that
specifies how you want JMP to display numeric values. See “Numeric Format Options,” p. 63, for
descriptions of options.
Figure 3.14 Column Info Window and Date-Time Formats
3 If you selected: