Hamster Matrix

Hamster Matrix is a gem providing a persistent immutable matrix for functional programming in Ruby. It is an extension for the popular Hamster gem. It creates a matrix by using nested Hamster Vectors.

It's great for keeping the board state in 2D video games, where the state must be modified while leaving references to the old state unchanged, such as when using a time travelling debugger or implementing undo functionality. It copies the interface from Ruby's Matrix class as much as possible.

Add this line to your application's Gemfile:

gem 'hamster-matrix'

And then execute:

$ bundle

Or install it yourself as:

$ gem install hamster-matrix

require 'hamster-matrix'
a = Hamster::Matrix[[1,0,0],[0,1,0],[0,0,1]]
b = a.set(2,2,'foo')
puts b
# [[1, 0, 0]
#  [0, 1, 0]
#  [0, 0, "foo"]]

puts a
#[[1, 0, 0]
# [0, 1, 0]
# [0, 0, 1]]

Implements the following methods replicating the behavior of Ruby's Matrix class as closely as possible

• []
• identity
• build
• column_vector
• columns
• diagonal
• I
• identity
• row_vector
• rows
• scalar
• unit

• ==
• []
• collect
• column
• column_count
• column_size
• column_vectors
• component
• element
• empty?
• get
• hash
• inspect
• map
• row
• row_count
• row_size
• row_vectors
• set
• square?
• to_a
• to_matrix
• to_s
• zero?

Bug reports and pull requests are welcome on GitHub at https://github.com/bradurani/hamster-matrix. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.