| stringWidth {grid} | R Documentation | 
These functions create a unit object describing the width or height of a string.
stringWidth(string) stringHeight(string) stringAscent(string) stringDescent(string)
string | 
 A character vector or a language object (as used for ‘plotmath’ calls.  | 
A unit object.
Paul Murrell
strwidth in the graphics package for more details of the
typographic concepts behind the computations.