enumerables and roman numerals examples

gistfile1.rb

array = ["9","8","7","6","5","4","3","2"]

array.length.times { |i| p array[i] }

array.each { |char| p char }

array.each_with_index { |char,i| p "#{char} || #{i}" }

matrix = Array.new(10) { Array.new(10) {"a"}}

matrix.each { |row| p row }

matrix.each_with_index do |row,row_num|
  row.each_with_index do |col, col_num|
    puts "row #{row_num}: #{row}"
    puts "col #{col_num}: #{col}"
    puts # just puts'ing a new line here
  end
end

example_array = [0,1,2,3,4,5,6]
# # take that array, and perform an operation on each element of the array, and put all of that in a new array

def doubler(array)
  bucket = []
  array.each { |number| bucket << number * 2 }
  bucket
end
# or .. 
def doubler(array)
  array.map { |number| number * 2 }
end

p doubler(example_array)

@cipher = {
  1000 => "M",
  500 => "D",
  100 => "C",
  50 => "L",
  10 => "X",
  5 => "V",
  1 => "I"
}

# MXXXVII
# number
# 1037  1x   how many, add that many, subtract that many
# 37    3x   ..
# 7     1x   ..
# 2     2x   ..
# 0     done

def num_to_roman(number)
  roman_numeral = ""
  @cipher.each do |unit,symbol|
    count = number / unit
    roman_numeral += symbol * count
    number -= count * unit
  end
  return roman_numeral
end