[lnkForumImage]
TotalShareware - Download Free Software
Confronta i prezzi di migliaia di prodotti.
Asp Forum
 Home | Login | Register | Search 


 

Forums >

comp.lang.ruby

Using ruby hash on array

Stuart Clarke

12/17/2008 10:21:00 PM

I would like to process some data from an array and using hash to
perform a count on one aspect of the data in the array. The array holds
lines of similarly formatted data like so

data A data B data C data D data E data F
data A data B data C data D data E data F
data A data B data C data D data E data F

data A is the identifier of each row full of data, data F contains a lot
of data which requires a regular expression which is passed to a method
for example:

"#{data F[/Name:\t(.+?)\r\n/, 1]}"

I am stuck writing the hash section of the code. The alogorithm is

if data A == 100
load data F reg expression into hash
end
count data F to determine the number of each name extracted by the
regular expression
print bob 6, sue 12, tim 1

I hope this makes sense and many thanks in advance
--
Posted via http://www.ruby-....
11 Answers

Louis-Philippe

12/17/2008 10:41:00 PM

0

[Note: parts of this message were removed to make it a legal post.]

I don't know if I got you right...
If a is the identifier, then your data structure could be something like:

hash = { 'data A' => ['data B', 'data C', 'data D', 'data E', 'data F'],
'data A' => ['data B', 'data C', 'data D', 'data E', 'data F'],
'data A' => ['data B', 'data C', 'data D', 'data E', 'data F'] }

where you could access a data A like hash['data A'] or with if
hash.has_key?('data A')
and data F with hash['data A'][4].

2008/12/17 Stuart Clarke <stuart.clarke1986@gmail.com>

> I would like to process some data from an array and using hash to
> perform a count on one aspect of the data in the array. The array holds
> lines of similarly formatted data like so
>
> data A data B data C data D data E data F
> data A data B data C data D data E data F
> data A data B data C data D data E data F
>
> data A is the identifier of each row full of data, data F contains a lot
> of data which requires a regular expression which is passed to a method
> for example:
>
> "#{data F[/Name:\t(.+?)\r\n/, 1]}"
>
> I am stuck writing the hash section of the code. The alogorithm is
>
> if data A == 100
> load data F reg expression into hash
> end
> count data F to determine the number of each name extracted by the
> regular expression
> print bob 6, sue 12, tim 1
>
> I hope this makes sense and many thanks in advance
> --
> Posted via http://www.ruby-....
>
>

Robert Klemme

12/18/2008 8:34:00 AM

0

2008/12/17 Stuart Clarke <stuart.clarke1986@gmail.com>:
> I would like to process some data from an array and using hash to
> perform a count on one aspect of the data in the array. The array holds
> lines of similarly formatted data like so
>
> data A data B data C data D data E data F
> data A data B data C data D data E data F
> data A data B data C data D data E data F

You do not say whether the format is delimited or fixed width.

> data A is the identifier of each row full of data, data F contains a lot
> of data which requires a regular expression which is passed to a method
> for example:
>
> "#{data F[/Name:\t(.+?)\r\n/, 1]}"
>
> I am stuck writing the hash section of the code. The alogorithm is
>
> if data A == 100
> load data F reg expression into hash
> end
> count data F to determine the number of each name extracted by the
> regular expression
> print bob 6, sue 12, tim 1

A framework:

Data = Struct.new :a, :b:, :c, :d, :e, :f

def Data.parse(line)
d = new(*line.strip.split(/\s+/))
d.f = Integer(d.f)
d
end

count = Hash.new 0

ARGF.each do |line|
data = Data.parse(line)
count[data.f[/Name:\t(.+?)\r\n/, 1]] += 1 if data.a == 100
end

count.each do |a, cnt|
printf "%20s %6d\n", a, cnt
end

Kind regards

robert

--
remember.guy do |as, often| as.you_can - without end

Stuart Clarke

12/18/2008 2:50:00 PM

0

Sorry for not being clear. I am actually parsing data from Windows event
logs and as a result the data is held in structured fields. Earlier in
my program I load the contents of a number of event logs into an array
and then ready the data using structs for example to read the ID number
- event.event_id more complicated for descriptions -
event.description[/Name:\t(.+?)\r\n/, 1]}

So what I would like to do is read my event log array and check for
specific event ID's (if event.event_id == 100).

If the if statement finds the ID 100 it reads name from
event.description. Everything mention thus far is working correctly.

When this is complete I then want to do a count on how many times each
name occurs e.g. bob = 2, sue = 12.
My thoughts were to load the event.description[/name:/] into a hash and
then do a count on each name in the hash and print it out.

Does this make more sense??


Louis-Philippe wrote:
> I don't know if I got you right...
> If a is the identifier, then your data structure could be something
> like:
>
> hash = { 'data A' => ['data B', 'data C', 'data D', 'data E', 'data F'],
> 'data A' => ['data B', 'data C', 'data D', 'data E', 'data F'],
> 'data A' => ['data B', 'data C', 'data D', 'data E', 'data F'] }
>
> where you could access a data A like hash['data A'] or with if
> hash.has_key?('data A')
> and data F with hash['data A'][4].
>
> 2008/12/17 Stuart Clarke <stuart.clarke1986@gmail.com>

--
Posted via http://www.ruby-....

Stuart Clarke

12/18/2008 2:50:00 PM

0


Sorry for not being clear. I am actually parsing data from Windows event
logs and as a result the data is held in structured fields. Earlier in
my program I load the contents of a number of event logs into an array
and then ready the data using structs for example to read the ID number
- event.event_id more complicated for descriptions -
event.description[/Name:\t(.+?)\r\n/, 1]}

So what I would like to do is read my event log array and check for
specific event ID's (if event.event_id == 100).

If the if statement finds the ID 100 it reads name from
event.description. Everything mention thus far is working correctly.

When this is complete I then want to do a count on how many times each
name occurs e.g. bob = 2, sue = 12.
My thoughts were to load the event.description[/name:/] into a hash and
then do a count on each name in the hash and print it out.

Does this make more sense??


Robert Klemme wrote:
> 2008/12/17 Stuart Clarke <stuart.clarke1986@gmail.com>:
>> I would like to process some data from an array and using hash to
>> perform a count on one aspect of the data in the array. The array holds
>> lines of similarly formatted data like so
>>
>> data A data B data C data D data E data F
>> data A data B data C data D data E data F
>> data A data B data C data D data E data F
>
> You do not say whether the format is delimited or fixed width.
>
>> end
>> count data F to determine the number of each name extracted by the
>> regular expression
>> print bob 6, sue 12, tim 1
>
> A framework:
>
> Data = Struct.new :a, :b:, :c, :d, :e, :f
>
> def Data.parse(line)
> d = new(*line.strip.split(/\s+/))
> d.f = Integer(d.f)
> d
> end
>
> count = Hash.new 0
>
> ARGF.each do |line|
> data = Data.parse(line)
> count[data.f[/Name:\t(.+?)\r\n/, 1]] += 1 if data.a == 100
> end
>
> count.each do |a, cnt|
> printf "%20s %6d\n", a, cnt
> end
>
> Kind regards
>
> robert

--
Posted via http://www.ruby-....

Robert Klemme

12/18/2008 2:56:00 PM

0

2008/12/18 Stuart Clarke <stuart.clarke1986@gmail.com>:

> Does this make more sense??

Did you actually look at my reply? You then would probably not have
sent the same answer three times...

robert


--
remember.guy do |as, often| as.you_can - without end

Stuart Clarke

12/18/2008 7:12:00 PM

0

Sorry I was getting to replying to you then got called off in a hurry. I
do not understand some of the code you have used as I am relatively new
to Ruby. Can you briefly outline the code, it would be greatly
appreciated.

Robert Klemme wrote:
> 2008/12/18 Stuart Clarke <stuart.clarke1986@gmail.com>:
>
>> Does this make more sense??
>
> Did you actually look at my reply? You then would probably not have
> sent the same answer three times...
>
> robert

--
Posted via http://www.ruby-....

Robert Klemme

12/18/2008 10:30:00 PM

0

On 18.12.2008 20:12, Stuart Clarke wrote:
> Sorry I was getting to replying to you then got called off in a hurry. I
> do not understand some of the code you have used as I am relatively new
> to Ruby. Can you briefly outline the code, it would be greatly
> appreciated.

I define a class holding the data you want to parse from the file via
Struct. I then also define a parse method on that class that will take
a line (basically a String) and parse it into a new data structure. You
will likely have to change these as field names like "a" and "b" are not
really telling and also you might want to do the parsing differently.

Then I initialize a Hash with default value 0. This is the value
returned for keys that are not present in the Hash.

Then the code reads from all input files (ARGF) named on the command
line (or stdin if there is no name), parses each line and increments the
counter for the entry.

Finally the Hash is sorted by key and key value pairs are printed.

Cheers

robert

--
remember.guy do |as, often| as.you_can - without end

Todd Benson

12/18/2008 10:52:00 PM

0

On Thu, Dec 18, 2008 at 1:12 PM, Stuart Clarke
<stuart.clarke1986@gmail.com> wrote:
> Sorry I was getting to replying to you then got called off in a hurry. I
> do not understand some of the code you have used as I am relatively new
> to Ruby. Can you briefly outline the code, it would be greatly
> appreciated.

> Robert Klemme wrote earlier:
> A framework:
>
> Data = Struct.new :a, :b:, :c, :d, :e, :f
(leave off the extra : after b :-)

Struct is an automatic way to define a simple class. There, he's
defining the structure of a class that he wants to call Data with the
use of Struct. So with this statement, we will have a class that has
attributes a, b, c, d, e, f, all with getters and setters, and (at
least in 1.8.7 AFAIK) an initialize method. For example...

MySimpleClass = Struct.new :instance_var
m = MySimpleClass.new "hi"
puts m.instance_var
m.instance_var = "bye"
puts m.instance_var
#hi
#bye

>
> def Data.parse(line)
> d = new(*line.strip.split(/\s+/))
> d.f = Integer(d.f)
> d
> end

There he is defining a class method called parse on the class Data.
This method returns a Data object filled with the info that was in the
string "line".

>
> count = Hash.new 0

As explained, that was a Hash initialization with a default value of 0

>
> ARGF.each do |line|
> data = Data.parse(line)
> count[data.f[/Name:\t(.+?)\r\n/, 1]] += 1 if data.a == 100
> end

Rack up the count if the conditions are met

>
> count.each do |a, cnt|
> printf "%20s %6d\n", a, cnt
> end

Print the darn thing out!

hth,
Todd

Stuart Clarke

12/21/2008 4:26:00 PM

0

Thanks for your help Todd. I have gone for a different approach which I
will post should it work.

I was wondering could you explain this code:

count.each do |a, cnt|
printf "%20s %6d\n", a, cnt
end


I have no idea what the %20s ...... is doing.

Many thanks

Todd Benson wrote:
> On Thu, Dec 18, 2008 at 1:12 PM, Stuart Clarke
> <stuart.clarke1986@gmail.com> wrote:
>> Sorry I was getting to replying to you then got called off in a hurry. I
>> do not understand some of the code you have used as I am relatively new
>> to Ruby. Can you briefly outline the code, it would be greatly
>> appreciated.
>
>> Robert Klemme wrote earlier:
>> A framework:
>>
>> Data = Struct.new :a, :b:, :c, :d, :e, :f
> (leave off the extra : after b :-)
>
> Struct is an automatic way to define a simple class. There, he's
> defining the structure of a class that he wants to call Data with the
> use of Struct. So with this statement, we will have a class that has
> attributes a, b, c, d, e, f, all with getters and setters, and (at
> least in 1.8.7 AFAIK) an initialize method. For example...
>
> MySimpleClass = Struct.new :instance_var
> m = MySimpleClass.new "hi"
> puts m.instance_var
> m.instance_var = "bye"
> puts m.instance_var
> #hi
> #bye
>
>>
>> def Data.parse(line)
>> d = new(*line.strip.split(/\s+/))
>> d.f = Integer(d.f)
>> d
>> end
>
> There he is defining a class method called parse on the class Data.
> This method returns a Data object filled with the info that was in the
> string "line".
>
>>
>> count = Hash.new 0
>
> As explained, that was a Hash initialization with a default value of 0
>
>>
>> ARGF.each do |line|
>> data = Data.parse(line)
>> count[data.f[/Name:\t(.+?)\r\n/, 1]] += 1 if data.a == 100
>> end
>
> Rack up the count if the conditions are met
>
>>
>> count.each do |a, cnt|
>> printf "%20s %6d\n", a, cnt
>> end
>
> Print the darn thing out!
>
> hth,
> Todd
--
Posted via http://www.ruby-....

Tim Greer

12/21/2008 7:01:00 PM

0

Stuart Clarke wrote:

> count.each do |a, cnt|
> printf "%20s %6d\n", a, cnt
> end
>
>
> I have no idea what the %20s ...... is doing.

It's just formatting/padding. It will right adjust the output on the
column 20 chars over.
--
Tim Greer, CEO/Founder/CTO, BurlyHost.com, Inc.
Shared Hosting, Reseller Hosting, Dedicated & Semi-Dedicated servers
and Custom Hosting. 24/7 support, 30 day guarantee, secure servers.
Industry's most experienced staff! -- Web Hosting With Muscle!