README
Raku Data::TypeSystems
This Raku package provides a type system for different data structures that are coercible to full arrays. Its code was originally developed in "Data::Reshapers", [AAp1].
Installation
From Zef ecosystem:
zef install Data::TypeSystem
From GitHub:
zef install https://github.com/antononcube/Raku-Data-TypeSystem.git
Usage examples
The type system conventions follow those of Mathematica's Dataset -- see the presentation "Dataset improvements".
Here we get the Titanic dataset, change the "passengerAge" column values to be numeric, and show dataset's dimensions:
use Data::ExampleDatasets;
my $url = 'https://raw.githubusercontent.com/antononcube/Raku-Data-Reshapers/main/resources/dfTitanic.csv';
my @dsTitanic = example-dataset($url, headers => 'auto');
@dsTitanic = @dsTitanic.map({$_<passengerAge> = $_<passengerAge>.Numeric; $_}).Array;
@dsTitanic.elems
# 1309
Here is a sample of dataset's records:
.say for @dsTitanic.pick(5)
# {id => 1097, passengerAge => 0, passengerClass => 3rd, passengerSex => male, passengerSurvival => died}
# {id => 1018, passengerAge => 20, passengerClass => 3rd, passengerSex => male, passengerSurvival => survived}
# {id => 31, passengerAge => 40, passengerClass => 1st, passengerSex => male, passengerSurvival => died}
# {id => 1030, passengerAge => -1, passengerClass => 3rd, passengerSex => male, passengerSurvival => died}
# {id => 126, passengerAge => -1, passengerClass => 1st, passengerSex => male, passengerSurvival => died}
Here is the type of a single record:
use Data::TypeSystem;
deduce-type(@dsTitanic[12])
# Struct([id, passengerAge, passengerClass, passengerSex, passengerSurvival], [Int, Int, Str, Str, Str])
Here is the type of single record's values:
deduce-type(@dsTitanic[12].values.List)
# Tuple([Atom((Int)), Atom((Str)), Atom((Str)), Atom((Str)), Atom((Int))])
Here is the type of the whole dataset:
deduce-type(@dsTitanic)
# Vector(Struct([id, passengerAge, passengerClass, passengerSex, passengerSurvival], [Int, Int, Str, Str, Str]), 1309)
Here is the type of "values only" records:
my @valArr = @dsTitanic>>.values>>.Array;
deduce-type(@valArr)
# Vector((Any), 1309)
Here is the type of the string values only records:
my @valArr = @dsTitanic.map({ $_.grep({ $_.value ~~ Str }).Hash })>>.values>>.Array;
.say for @valArr.pick(4);
# [1st male died]
# [3rd male died]
# [male died 3rd]
# [died 3rd male]
deduce-type(@valArr);
# Vector(Vector(Atom((Str)), 3), 1309)
References
[AAp1] Anton Antonov, Data::Reshapers Raku package, (2021), GitHub/antononcube.