Question

I am working on business analytics application, where I need to fetch some data on per hour basis of a particular month. for example I wanna get the data from jun 01 2012 to jun 30 2012 and I need to fetch the data of every hour between those days.
Like 12:00 13:00,13:00-14:00 ….etc.

How do I do it. Kindly let me know. Using 1.8.7 platform.

Answer 1

If you are using Rails there is a Date method step: http://corelib.rubyonrails.org/classes/Date.html#M001273

---

On pure ruby just write simple loop:

t=Time.new(2012,01,01,0,0,0) #start time
max_time=Time.new(2012,01,31,23,59,59) #end time
step=60*60 #1hour
while t<=max_time
     p t #your code here
     t += step
end

To simplify use this ruby extension:

module TimeStep

  def step(limit, step)  # :yield: time
    t = self
    op = [:-,:<=,:>=][step<=>0]
    while t.__send__(op, limit)
       yield t
       t += step
    end
    self
  end
end

Time.send(:include, TimeStep) #include the extension

Usage:

t=Time.new(2012,01,01,0,0,0)
t.step(Time.new(2012,01,31,23,59,59),3600) do |time|
  puts time
end

You can also down-iterate:

t=Time.new(2012,01,31)
t.step(Time.new(2012,01,1),-3600) do |time|
   puts time
end