selectSome              package:Biobase              R Documentation

Extract elements of a vector for concise rendering

Description:

     Extract the first and last several elements of a vector for
     concise rendering; insert ellipses to indicate elided elements.
     This function is primarily meant for developer rather than
     end-user use.

Usage:

     selectSome(obj, maxToShow=5)

Arguments:

     obj: A vector.

maxToShow: The number of elements (including "...") to render.

Details:

     This function can be used in 'show' methods to give users
     exemplars of the tokens used in a vector.  For example, an
     'ExpressionSet' built from a yeast experiment might have features
     enumerated using systematic gene names (e.g., YPR181C) or standard
     gene names (e.g., SEC23).  The 'show' method for 'ExpressionSet'
     uses 'selectSome' to alert the user to the tokens used, and
     thereby to indicate what vocabulary must be understood to work
     with the feature names.

Value:

     A string vector with at most 'maxToShow' plus 1 elements, where an
     ellipsis ("...") is included to indicate incompleteness of the
     excerpt.

Author(s):

     Martin Morgan <mtmorgan@fhcrc.org>

Examples:

     selectSome(1:20)

