nl_tokens: Divide and round .
pl_tokens: static public BigDecimal divideRound ( final BigDecimal x , final BigDecimal y ) { /* The estimation of the relative error in the result is |err(y)/y|+|err(x)/x|
           */ MathContext mc = new MathContext ( Math . <mask> ( x . precision ( ) , y . precision ( ) ) ) ; return x . divide ( y , mc ) ; }