RGB to Hex in Lua

gistfile1.lua

-- passing a table like {255, 100, 20}

function application:rgbToHex(rgb)
	local hexadecimal = '0X'

	for key, value in pairs(rgb) do
		local hex = ''

		while(value > 0)do
			local index = math.fmod(value, 16) + 1
			value = math.floor(value / 16)
			hex = string.sub('0123456789ABCDEF', index, index) .. hex			
		end

		if(string.len(hex) == 0)then
			hex = '00'

		elseif(string.len(hex) == 1)then
			hex = '0' .. hex
		end

		hexadecimal = hexadecimal .. hex
	end

	return hexadecimal
end

im kinda noob at coding but here is my solution:

rgb = {235,123,175}
function convert_to_hex (rgb)
    local hex = ""
    for i = 1 , #rgb do
        local hex_table = {"0","1","2","3","4","5","6","7","8","9","A","B","C","D","E","F"}
        local num =  rgb[i]/16 
        local whole = math.floor( num )
        local remainder = num - whole
        hex = hex .. hex_table[whole+1] .. hex_table[remainder*16 + 1]
    end
    return hex
end

print(convert_to_hex(rgb))

That's a frightening piece of code you wrote up there