This optional field allows you a convenient method to specify variables that are numbered sequentially or contain a common prefix when there are more than can be conveniently selected by highlighting and using the button.
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• Common prefix (subset). Specify var1-var1000 to select columns named var1 through var1000, inclusively.
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• Variable position within data set (all variable types). If your data set columns are ordered as {e20, b15, a25, d30, c10}, then specify b15--d30 to select the variables b15, a25, and d30.
• Variable position within data set (type-specific). If your data set columns are ordered as {e20, b15, a25, d30, c10}, and all variables are numeric except for a25 (which is character), then specify b15-numeric-d30 to select the variables b15 and d30. Likewise, specify b15-character-d30 to select the variable a25.
• All variables of a specific type. Specify _numeric_ to select all numeric variables, and _character_ to select all character variables.
• Caution: Using the common prefix notation (_:) could potentially include variables created by SAS procedures, in spite of your intention otherwise. Therefore, it is strongly recommended that you either avoid this notation, or specify the longest prefix possible before the colon to avoid capturing extraneous variables.