Ranges
******

 -- Range: (void)
 -- Range: (const Range &R)
 -- Range: (double B, double L)
 -- Range: (double B, double L, double I)

 -- double: base (void) const
 -- double: limit (void) const
 -- double: inc (void) const

 -- void: set_base (double B)
 -- void: set_limit (double L)
 -- void: set_inc (double I)

 -- int: nelem (void) const

 -- double: min (void) const
 -- double: max (void) const

 -- void: sort (void)

 -- ostream&: operator << (ostream &OS, const Range &R)
 -- istream&: operator >> (istream &IS, Range &R)

 -- void: print_range (void)