Thank you very much !
Actually , I refer "round_to" in a class Fixnum below my main codes. I don't see any error.
It's my new knowledge about sprintf("%.2f", 1.23456)
[ruby]class Fixnum
def abs
rx = self
if rx < 0
rx = -rx
end
return rx
end
def to_meter
ufactor = 1.m
rx = (self) / ufactor
return rx
end
def round_to(x)
(self * 10**x).round.to_f / 10**x
end
def ceil_to(x)
(self * 10**x).ceil.to_f / 10**x
end
def floor_to(x)
(self * 10**x).floor.to_f / 10**x
end
def rad_to_deg
(self / Math;;PI) * 180.0
end
def deg_to_rad
(self * Math;;PI) / 180.0
end
def comma_format
s = self.to_s
if s.include? ?.
pre, post = s.split '.'
"#{pre.reverse.gsub( /\d{3}(?=\d)/, '\&,' ).reverse}.#{post}"
else
s.reverse.gsub( /\d{3}(?=\d)/, '\&,' ).reverse
end
end
end
[/ruby][/code]