IRB Practice (Day 2)

2.2.0 :001 > def sayhi
2.2.0 :002?>   puts "HI!"
2.2.0 :003?>   end
 => :sayhi 
2.2.0 :004 > def greeting(name)
2.2.0 :005?>   puts "Hi, #{name}."
2.2.0 :006?>   end
 => :greeting 
2.2.0 :007 > greeting("Bill")
Hi, Bill.
 => nil 
2.2.0 :008 > [1,2,3,4]
 => [1, 2, 3, 4] 
2.2.0 :009 > [1,2,3,4].sort
 => [1, 2, 3, 4] 
2.2.0 :010 > array = [1,2,3,5]
 => [1, 2, 3, 5] 
2.2.0 :011 > array.sort
 => [1, 2, 3, 5] 
2.2.0 :012 > array = [123,23,3,5]
 => [123, 23, 3, 5] 
2.2.0 :013 > array.sort
 => [3, 5, 23, 123] 
2.2.0 :014 > array
 => [123, 23, 3, 5] 
2.2.0 :015 > array.sort!
 => [3, 5, 23, 123] 
2.2.0 :016 > array
 => [3, 5, 23, 123] 
2.2.0 :017 > an_array = ["James","Lucy","John","Katie"]
 => ["James", "Lucy", "John", "Katie"] 
2.2.0 :018 > an_array.each {|w| puts w}
James
Lucy
John
Katie
 => ["James", "Lucy", "John", "Katie"] 
2.2.0 :019 > Math.sqrt(1282)
 => 35.805027579936315 
2.2.0 :020 > Time.now
 => 2016-04-26 11:01:33 -0400 
2.2.0 :021 > Time.tomorrow
NoMethodError: undefined method `tomorrow' for Time:Class
	from (irb):21
	from /Users/gabrielrambert/.rvm/rubies/ruby-2.2.0/bin/irb:11:in `<main>'
2.2.0 :022 > Time.yesterday
NoMethodError: undefined method `yesterday' for Time:Class
	from (irb):22
	from /Users/gabrielrambert/.rvm/rubies/ruby-2.2.0/bin/irb:11:in `<main>'
2.2.0 :023 > t = Time.now
 => 2016-04-26 11:02:46 -0400 
2.2.0 :024 > t.day
 => 26 
2.2.0 :025 >