How to turn decimals into hex without prefix `0x`

Question

def tohex(r, g, b):
    #your code here :)
    def hex1(decimal):
        if decimal < 0:
            return '00'
        elif decimal > 255:
            return 'FF'
        elif decimal < 17:
            return  '0'+ hex(decimal)[2:]
        else:
            return inthex(decimal)[2:]
    return (hex1(r) + hex1(g) + hex1(b)).upper()
print rgb(16 ,159 ,-137)

I define a new method to get my hex numbers. But when it comes to (16 ,159 ,-137), I got 0109F00 instead of 019F00. Why there is an extra 0？

Answer 1

You have an extra zero because the line should be elif decimal < 16 not 17.

Use format strings¹:

def rgb(r,g,b):
    def hex1(d):
        return '{:02X}'.format(0 if d < 0 else 255 if d > 255 else d)
    return hex1(r)+hex1(g)+hex1(b)

print rgb(16,159,-137)

Output:

109F00

¹https://docs.python.org/2.7/library/string.html#format-specification-mini-language