perl, populating a hash from a subroutine call on file input, array input, or no input

Question

I made the class as follows:

package Tool;

sub new {

  my ( $class, %args ) = @ARG;

  my $self = bless {
  #hash reference  
    _ToolParameters => { }

  }, $class;

  return $self;

}

I then want to create an instance of this class:

my $Object = Tool->new();

then, I'd like to read from a textfile or array to populate the hash and call it as follows:

from an array:    $Object->ImportData(\@Arraylist);
from a textfile:  $Object->ImportData(textfile.csv);

in this function ImportData, I would like to read my key from an array list which will strictly be the ID#, or from the CSV file, it'd be strictly the first column that is the ID# or to be able to insert the values manually:

*I want it such that the ID# = the key.

I'm thinking of also generating at least one parameter field for this key by default, and assigning it a default value 0.

Basically when I return from this list I'll have something suggested by ikegami earlier, like:

$self->{_ToolParameters}{$ID#1}{test_parameter_1} = $value;
$self->{_ToolParameters}{$ID#2}{test_parameter_1} = $value;

If I'm accepting an array, the input is as follows:

@Arraylist = (key1 ,..., keyN);

as this is part of a larger program, I plan to run each key through a series of a number of 'X' test-suites, these test suites I plan to give the name "parameterX", X being the number of the test-suite. I take the first test-suite as given, so my desired output should be that in the object, i'd have by default (before pushing on any more parameters):

*the default value for the 'value' is zero, because I have not run the testsuite, I am just initializing the field

key1 -> first_test ->0
key2 -> first_test ->0
.
.
keyN ->     first_test ->            0
(key)  (test_parameter_1)  (value of test_parameter_1)

I want this returned to the object such that I can later pass more tests into the hash, such that for example I can have:

key1 -> first_test -> 0
     -> second_test -> 0

Similarly, from the textfile, all I care about are the columns which represent the keys, or IDs.

I guess my confusion was how to make this assignment reliably such that I have an object that contains a list of expandable valued pairings, but writing this out helped me resolve much of it.

This is where I require some guidance.

sub ImportData{
 my $a = shift;

 if($a eq /*.csv$/i )
{ #textfile case

  my @get_first_col = some kind of column dump; #keys, probably a while loop

  foreach $key (@get_first_col)
  {
  push($self->{_ToolParameters}{$key}{test_parameter_1} = 0);
  }
}
elseif($a)
{ #array case - want to reliably check if we're handling an array
  foreach (@{a})
  {
  push($self->{_ToolParameters}{$_}{test_parameter_1} = 0);
  }
}
else
{#case of manual input
my $a = <STDIN>
push($self->{_ToolParameters}{$_}{test_parameter_1} = 0);
}

}

Why not make one of the fields of the object a hash that maps `$key` to `[$parameter, $parameter2]`? — melpomene, Oct 14 '16 at 21:34
show the input text file (a short example of it). @ikegami has it, the answer just needs some real input data — stevieb, Oct 15 '16 at 00:26
I've seen you updated your question, but you've made it all the more confusing (e.g. by saying you only have `$key`, but that you want to use `$ID` and `$value`). I repeat: show your inputs or the desired output for those inputs. I've demonstrated how to do this in my answer. Tag me in a comment when you do, and I'll update my answer. — ikegami, Oct 16 '16 at 22:32
@ikegami , I think I have been able to supply what you asked, is this a sensible approach? Is this doing what I think it to be doing? Next I'll run some test-cases in my environment to see. — Plexus, Oct 16 '16 at 23:35

ikegami · Accepted Answer · 2016-10-15T01:08:35.057

1

It's unclear what you want.

To produce

{
    key1 => {
        parameter1 => 0,
        parameter2 => 0,
    },
    key2 => {
        parameter1 => 0,
        parameter2 => 1,
    },
}

given

my @rows = (
    [ 'key1', 0, 0 ],
    [ 'key2', 0, 1 ],
);

you want

$self->{$key}{parameter1} = $parameter;
$self->{$key}{parameter2} = $parameter2;

or

$self->{_ToolParameters}{$key}{parameter1} = $parameter;
$self->{_ToolParameters}{$key}{parameter2} = $parameter2;

edited Oct 15 '16 at 01:08

answered Oct 14 '16 at 21:59

ikegami

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this is how to do it, but I'm confident that if/when the OP provides real input data, this'll be updated to reflect it. – stevieb Oct 15 '16 at 00:28
It be nice to take the key to be an ID# – Plexus Oct 16 '16 at 20:13
It be nice to take the key to be an ID# then for the ID# set a parameter like "test_one_passed", then set a value to it to begin = 0 but the textfile or input would only provide the ID#, and by default i'd begin with just this "test_one_passed", but later populate the hash such that the ID would have to pass more tests. – Plexus Oct 16 '16 at 20:16
No idea what you mean. See how I provided the inputs and the desired outputs? Edit your question to provide the correct versions of these. – ikegami Oct 16 '16 at 20:17

perl, populating a hash from a subroutine call on file input, array input, or no input

1 Answers1