Hi all, I hope someone can point me in the right direction. I am looking for some sample code to help with writing some code for scheduling maintenance for machinery. The idea is that, like a car, this machinery needs maintenance either at certain intervals or after a certain number of hours of use (whichever is sooner). I am not sure how best to manage the time measurements (DateTime or Time?) or how to build the business rules to do the measurements and comparisons robustly. I wondered whether anyone here could direct me to an example. Thanks, Ian. -- --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
it all depends on your machine. nobody can tell you what''s right (or even the best) for you. you gotta decide for yourself. to show you some alternatives: - you could just work with cron-jobs. - you could use backgrounDRb or workling/starling to schedule your own processes. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
On Mon, Mar 2, 2009 at 10:50 AM, Ian Piper <ianpiper-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:> I am not sure > how best to manage the time measurements (DateTime or Time?) or how to > build the business rules to do the measurements and comparisons > robustly. > > I wondered whether anyone here could direct me to an example.If you don''t need increments smaller than 1 day, I prefer to use the Date class. I find it easier than Time to work with: * no ambiguity over "now" being a different date in different time zones etc * easier to compare date_1 == date_2 http://ruby-doc.org/stdlib/libdoc/date/rdoc/classes/Date.html A few simplistic examples:>> date = Date.today=> Mon, 02 Mar 2009>> next_month = date + 1.month=> Thu, 02 Apr 2009>> date = Date.new 2009,01,31=> Sat, 31 Jan 2009>> next_month = date + 1.month=> Sat, 28 Feb 2009 # automatic rounding down to valid date>> date = Date.new 2008,02,29=> Fri, 29 Feb 2008>> next_year = date + 1.year=> Sat, 28 Feb 2009 # automatic rounding down to valid date>> four_years_later = date + 4.year=> Wed, 29 Feb 2012 Always be careful with comparing dates near the end of the months as months have a variable length. Easier comparison of date_1 == date_2 (compared to time_1 == time_2)>> date_1 = Date.today=> Mon, 02 Mar 2009>> date_2 = Date.today=> Mon, 02 Mar 2009>> date_1 == date_2=> true>> time_1 = Time.now=> Mon Mar 02 11:24:59 +0100 2009>> time_2 = Time.now=> Mon Mar 02 11:25:06 +0100 2009>> time_1 == time_2=> false HTH, Peter --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
On 2 Mar 2009, at 10:28am, Peter Vandenabeele wrote:> > On Mon, Mar 2, 2009 at 10:50 AM, Ian Piper <ianpiper-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote: >> I am not sure >> how best to manage the time measurements (DateTime or Time?) or how >> to >> build the business rules to do the measurements and comparisons >> robustly. >> >> I wondered whether anyone here could direct me to an example. > > If you don''t need increments smaller than 1 day, I prefer to use the > Date class. > I find it easier than Time to work with: > * no ambiguity over "now" being a different date in different time > zones etc > * easier to compare date_1 == date_2 > > http://ruby-doc.org/stdlib/libdoc/date/rdoc/classes/Date.htmlThanks Peter, Those are good examples. You mention using Date for increments that are not smaller than one day. In fact my situation is a hybrid, since the machinery may be running at intervals over several days (so I would need to track a usage event that spans days) but I need to record the total number of hours of use during that time. From what I can see the DateTime class allows for this. I suppose what I am really asking here is under what circumstances would I use the Time class: using DateTime always gives me more information doesn''t it? Ian. -- --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---