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rgb to hex conversion

admin 11月 13, 2020 0

The rgb() method is incomplete. Complete the method so that passing in RGB decimal values will result in a hexadecimal representation being returned. The valid decimal values for RGB are 0 - 255. Any (r,g,b) argument values that fall out of that range should be rounded to the closest valid value.

The following are examples of expected output values:

rgb(255, 255, 255) # returns FFFFFF
rgb(255, 255, 300) # returns FFFFFF
rgb(0,0,0) # returns 000000
rgb(148, 0, 211) # returns 9400D3

Answers:

def (r, g, b)
  
  rgb_list = [r,g,b].map {|item| 
    if item < 0
      0
    elsif item >255
      255
    else
      item
    end
  }
  rgb_list.inject("") {|str,item| str + item.to_s(16).rjust(2,"0")}.swapcase
end


def (r, g, b)
  "%.2X%.2X%.2X" % [r,g,b].map{|i| [[i,255].min,0].max}
end

def (r, g, b)
  [r, g, b].map do |c|
    if c <= 0 
      "00"
    elsif c > 255
      "FF"
    else
      c.to_s(16).upcase    
    end
  end.join('')
end

def (r, g, b)
  [r, g, b].map{ |n| [0, n, 255].sort[1].to_s(16).upcase.rjust(2, "0")}.join
end

def (r, g, b)
  [r, g, b].map do |i|
    i = 0 if i < 0
    i = 255 if i > 255
    i.to_s(16).rjust(2, '0').upcase
  end.join
end