z2cent: Express z-scores as centile character strings for plotting
Description
Converts z-scores, typically defining centiles in a growth chart, to
character strings that can be used to label the centile curves.
Usage
z2cent(z)
Arguments
z
a scalar or vector of z-scores.
Value
A character string is returned, the same length as z. Z-scores in
the range +/- 3.3 are converted to centiles with one or two significant
figures (lower tail) or to their complement (upper tail). For z-scores
exceeding 3.3 in absolute value the character consists of "SDS" appended to
the z-score rounded to one decimal place.