r#help arg;cols;rows;vec
 vec#(rows#1YRhelptab),cols#Rarg#,arg
 $(cols>3)/sym
 r#helptab[(cols=+/(vecRarg)=vecYhelptab)/Irows;]
 $(0^=1YRr)/0
sym:r#helptab[(cols=+/(vecRarg)=vecY4`Ohelptab)/Irows;]
 $0
"the argument (arg) can be either a symbol (e.g. 'Y'), or a function name,
"(e.g. 'shape').  the help function will list any lines in helptab that
"pertain to the specified symbol or function name.