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How do I perform vector addition in Ruby?

How do I perform vector addition in Ruby so that

[100, 100] + [2, 3]

yields

[102, 103]

(instead of joining two arrays)?

Or it can be another operator too, such as 

[100, 100] @ [2, 3]

or 

[100, 100] & [2, 3]
Solution

  • See the Vector class:

    require "matrix"

x = Vector[100, 100]
y = Vector[2, 3]
print x + y

E:\Home> ruby t.rb
Vector[102, 103]

    See vectorops for additional operations on vectors:

    … the following operations work like expected

      v1 = Vector[1,1,1,0,0,0]
  v2 = Vector[1,1,1,1,1,1]

  v1[0..3]
  # -> Vector[1,1,1]

  v1 += v2
  # -> v1 == Vector[2,2,2,1,1,1]

  v1[0..3] += v2[0..3]
  # -> v1 == Vector[2,2,2,0,0,0]

  v1 + 2
  # -> Vector[3,3,3,1,1,1]

    See also vectorops.

    Note that matrix is no longer a default gem starting with Ruby 3.1.0. Thanks to Dan Murphy for mentioning this.