54 lines
1.2 KiB
Markdown
54 lines
1.2 KiB
Markdown
---
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title: Ruby Arrays
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---
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## Ruby Arrays
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An array represents a list of values. The individual values are often called "elements" of the array. To make an array in Ruby, use square brackets and separate values with commas:
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```ruby
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my_array = [1, 2, 3, 4, 5]
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```
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You can also create an empty array by using the 'new' method in the 'Array' class:
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```ruby
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my_array = Array.new
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```
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That first example is an array of numbers, but a Ruby array can contain values of different types, even other arrays:
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```ruby
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mixed_array = [5, "Hello World", true, [1,2,3]]
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```
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You can access the elements of an array with square brackets and numerical indexes. Notice that the first element is at index 0, not 1:
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```ruby
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mixed_array[0] # 5
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mixed_array[1] # "Hello World"
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mixed_array[2] # true
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```
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You can check how many elements an array has with the `length` method:
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```ruby
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mixed_array.length # 4
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[].length # 0
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```
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You can check the first element of an array with the `first` method:
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```ruby
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mixed_array.first # 5
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```
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You can check the last element of an array with the `last` method:
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```ruby
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mixed_array.last # [1,2,3]
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```
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#### More Information:
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[Ruby array documentation](https://ruby-doc.org/core-2.4.2/Array.html)
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