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# 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](https://github.com/hamstergem/hamster/) gem. It creates a matrix by using nested Hamster [Vectors](http://www.rubydoc.info/github/hamstergem/hamster/master/Hamster/Vector).  

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](http://ruby-doc.org/stdlib-2.0.0/libdoc/matrix/rdoc/Matrix.html) class as much as possible.


## Installation

Add this line to your application's Gemfile:

```ruby
gem 'hamster-matrix'
```

And then execute:

    $ bundle

Or install it yourself as:

    $ gem install hamster-matrix

## Usage

```ruby
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](http://ruby-doc.org/stdlib-2.0.0/libdoc/matrix/rdoc/Matrix.html) class as closely as possible

### Class Methods
 - []
 - identity
 - build
 - column_vector
 - columns
 - diagonal
 - I
 - identity
 - row_vector
 - rows
 - scalar
 - unit

### Instance Methods
 - ==
 - []
 - 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?

## Contributing

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](contributor-covenant.org) code of conduct.