public String toString( String separator )
public String toString( )
	public String toString( String separator )	{		if ( denominator != 1 )		{			StringBuffer buffer = new StringBuffer( );			// both negative: no sign			if ( ( numerator * denominator ) < 0 )				buffer.append( "-" );			buffer.append( Math.abs( numerator ) );			buffer.append( separator );			buffer.append( Math.abs( denominator ) );			return buffer.toString( );		}		else			return String.valueOf( numerator );	}