Function: sizedigit
Section: conversions
C-Name: sizedigit
Prototype: lG
Help: sizedigit(x): maximum number of decimal digits minus one of (the
 coefficients of) x.
Doc:
 outputs a quick bound for the number of decimal
 digits of (the components of) $x$, off by at most $1$. If you want the
 exact value, you can use \kbd{\#Str(x)}, which is slower.
