Re: numeric?

I've already sorted them into classes and objects, so instance variables
are created for every antenna and other such things.

On Thu, Dec 27, 2012 at 5:27 PM, Robert Klemme
<[e-mail]>wrote:

> On Thu, Dec 27, 2012 at 11:32 PM, Brandon Weaver
> <[e-mail]> wrote:
> > Sorry, I wasn't very clear. I was typing most of that from my Phone.
> >
> > I'm writing scripts for a wireless ISP, and we use several different
> types
> > of antennas. They're monitored in several different ways,
> > SSH/Telnet/SNMP/etc. Annoyingly they all return different values for
> null,
> > but they're always string based, so a numeric evaluation will quickly
> yield
> > whether the device is working or down. I could write a more correct
> solution
> > in the sense that it's less of a hack with individual classes for every
> > antenna, but the goal is that if we ever get a new type of equipment
> that it
> > will take minimal coding to get a framework up and running for it.
>
> What's wrong then to use Float() as suggested?
>
> begin
>   f = Float(from_device)
>   printf "Read value %20.5f\n", f
> rescue ArgumentError => e
>   # not a float
> end
>
> An alternative would be to convert non numeric values to nil - if you
> want safe null handling:
>
> f = Float(from_device) rescue nil
>
> > One such example is min, max, and avg for multiple fields such as Signal
> to
> > Noise, Retransmit, and etc. I used instance_variable_get to dynamically
> > evaluate fields. There are ways in which I could probably use more of
> > Enumerator, and I still need to sort that out some more.
>
> You could use Structs and then:
>
> irb(main):001:0> S=Struct.new :a, :b, :c
> => S
> irb(main):002:0> S.members
> => [:a, :b, :c]
> irb(main):003:0> S.new.members
> => [:a, :b, :c]
> irb(main):004:0> s = S.new 1,2,3
> => #<struct S a=1, b=2, c=3>
> irb(main):005:0> s.members
> => [:a, :b, :c]
> irb(main):006:0> s.each_pair {|k,v| printf "%p=%p\n", k, v}
> :a=1
> :b=2
> :c=3
> => #<struct S a=1, b=2, c=3>
>
> Kind regards
>
> robert
>
> --
> remember.guy do |as, often| as.you_can - without end
> http://blog.rubybestpractices.com/
>
>