CODEWITHSUNDEEP
arraysruby
Steven Aguilar
Steven Aguilar

Reputation: 3049

turn a number into an array of integers up to that number starting from 1

So I am trying to turn a number into an array of integers up to that number starting at one. So for example if the number is 9 I want an array to be nums = [1,2,3,4,5,6,7,8,9] Is there any built-in method for this? I try the following:

 arr = [] 
(1..9).each do |num|   
  arr << num 
end

But this gives me the following output. arr = [0, 1, 2, 3, 4, 5, 6, 7, 8, 1, 2, 3, 4, 5, 6, 7, 8, 9]

Upvotes: 0

Views: 108

Answers (5)

krishna raikar
krishna raikar

Reputation: 2675

Use something like this:

(1..x).to_a

Where x can be any number.

Upvotes: 0

Sagar Pandya
Sagar Pandya

Reputation: 9497

A neat trick:

[*1..9]
 #=> [1, 2, 3, 4, 5, 6, 7, 8, 9]

And as we're in Ruby land, some alternatives:

Array.new 9 { |i| i + 1 }
 #=> [1, 2, 3, 4, 5, 6, 7, 8, 9]

9.times.with_object [] { |i,o| o << i + 1 }
 #=> [1, 2, 3, 4, 5, 6, 7, 8, 9]

(1..Float::INFINITY).take 9
 #=> [1, 2, 3, 4, 5, 6, 7, 8, 9]

Upvotes: 2

whodini9
whodini9

Reputation: 1434

num = 9
(1..num).to_a
# => [1, 2, 3, 4, 5, 6, 7, 8, 9]

or

Array(1..num)

Upvotes: 2

moveson
moveson

Reputation: 5213

Using the .. operator creates a Range, and Per the docs, a Range, like any other Enumerable object, can be converted directly into an Array:

(1..9).to_a
#=> [1, 2, 3, 4, 5, 6, 7, 8, 9]

You might be interested to know that you can also do this with a Range built using String values:

('a'..'e').to_a
#=> ["a", "b", "c", "d", "e"]

Upvotes: 4

Greg
Greg

Reputation: 6628

Here's a way to do it: 

(1..9).map(&:itself)

Upvotes: 0

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