RedAmber
A simple dataframe library for Ruby (experimental)
Requirements
gem 'red-arrow', '>= 7.0.0'
gem 'red-parquet', '>= 7.0.0' # if you use IO from/to parquet
gem 'rover-df', '~> 0.3.0' # if you use IO from/to Rover::DataFrameInstallation
Add this line to your Gemfile:
gem 'red_amber'And then execute:
bundle installOr install it yourself as:
gem install red_amber
RedAmber::DataFrame
Represents a set of data in 2D-shape.
require 'red_amber'
require 'datasets-arrow'
penguins = Datasets::Penguins.new.to_arrow
puts RedAmber::DataFrame.new(penguins).tdr
# =>
RedAmber::DataFrame : 344 x 8 Vectors
Vectors : 5 numeric, 3 strings
# key type level data_preview
1 :species string 3 {"Adelie"=>152, "Chinstrap"=>68, "Gentoo"=>124}
2 :island string 3 {"Torgersen"=>52, "Biscoe"=>168, "Dream"=>124}
3 :bill_length_mm double 165 [39.1, 39.5, 40.3, nil, 36.7, ... ], 2 nils
4 :bill_depth_mm double 81 [18.7, 17.4, 18.0, nil, 19.3, ... ], 2 nils
5 :flipper_length_mm uint8 56 [181, 186, 195, nil, 193, ... ], 2 nils
6 :body_mass_g uint16 95 [3750, 3800, 3250, nil, 3450, ... ], 2 nils
7 :sex string 3 {"male"=>168, "female"=>165, nil=>11}
8 :year uint16 3 {2007=>110, 2008=>114, 2009=>120}DataFrame model
For example, DataFrame#pick accepts keys as an argument and returns a sub DataFrame.
df = penguins.pick(:body_mass_g)
# =>
#<RedAmber::DataFrame : 344 x 1 Vector, 0x000000000000fa14>
Vector : 1 numeric
# key type level data_preview
1 :body_mass_g int64 95 [3750, 3800, 3250, nil, 3450, ... ], 2 nilsDataFrame#assign can accept a block and create new variables.
df.assign do
{:body_mass_kg => penguins[:body_mass_g] / 1000.0}
end
# =>
#<RedAmber::DataFrame : 344 x 2 Vectors, 0x000000000000fa28>
Vectors : 2 numeric
# key type level data_preview
1 :body_mass_g int64 95 [3750, 3800, 3250, nil, 3450, ... ], 2 nils
2 :body_mass_kg double 95 [3.75, 3.8, 3.25, nil, 3.45, ... ], 2 nilsOther DataFrame manipulating methods like pick, drop, slice, remove and rename also accept a block.
See DataFrame.md for details.
RedAmber::Vector
Class RedAmber::Vector represents a series of data in the DataFrame.
penguins[:species]
# =>
#<RedAmber::Vector(:string, size=344):0x000000000000f8e8>
["Adelie", "Adelie", "Adelie", "Adelie", "Adelie", "Adelie", "Adelie", "Adelie", ... ]Vectors accepts some functional methods from Arrow.
See Vector.md for details.
TDR concept
I named the data frame representation style in the model above as TDR (Transposed DataFrame Representation). See TDR.md for details.
Development
git clone https://github.com/heronshoes/red_amber.git
cd red_amber
bundle install
bundle exec rake testLicense
The gem is available as open source under the terms of the MIT License.
