Converting an integer to a sequence of letters using a function

Question

I want to create a function that takes an integer (say 234) and returns it as letters (cde).

I have managed to form some code that takes the number and separates it into its numeric components

def toLetter(n):
    x = str(n)
    for elem in x:
        print(elem)
    d = {0 : 'a', 1 : 'b', 2 : 'c', 3 : 'd', 4 : 'e', 5 : 'f', 6 : 'g', 7 : 'h', 8 : 'i', 9 : 'j'}
    for n in x:
        d[n]

toLetter(234)

But I am really struggling with;

how to map the dictionary onto the number and
get it to return it as:

cde

rather than

c
d
e

Any help would be greatly appreciated. I am new so this may be trivial but I have come here as last resort.

Does this answer your question? [How to print without a newline or space](https://stackoverflow.com/questions/493386/how-to-print-without-a-newline-or-space) — Mr. T, Feb 18 '22 at 14:13

score 1 · Answer 1 · answered Feb 18 '22 at 14:17

You should use strings as keys in your dictionary.

A simple way, use a generator/comprehension:

def toLetter(num):
    d = dict(zip('0123456789', 'abcdefghij'))
    return ''.join(d[i] for i in str(num))

Even better, use a translation table:

def toLetter(num):
    t = str.maketrans('0123456789', 'abcdefghij')
    return str(num).translate(t)

example:

toLetter(123)
# 'bcd'

score 0 · Accepted Answer · answered Feb 18 '22 at 14:16

0

So, in order to select the elements in the dictionary you have to convert the digits back to integers. Also, to create the final answer I would simply append each letter to a string and print the final string:

def toLetter(n):
    d = {0 : 'a', 1 : 'b', 2 : 'c', 3 : 'd', 4 : 'e', 5 : 'f', 6 : 'g', 7 : 'h', 8 : 'i', 9 : 'j'}
    
    x = str(n)
    result = ''
    
    for elem in x:
        result = result + d[int(elem)]
    
    print(result)

toLetter(234)

Output:

cde

answered Feb 18 '22 at 14:16

JANO

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@constar99 it is however a bit wasteful to perform the double conversion… directly use strings as keys, also repeated string concatenation is not recommended – mozway Feb 18 '22 at 14:32
@mozway Of course you are right, but I think in this case an understandable and readable solution is more helpful than the most efficient one. – JANO Feb 18 '22 at 14:38
I disagree here, it is never too early to learn good practices, this is precisely the time to learn those things when you're a beginner ;) – mozway Feb 18 '22 at 14:40
Regarding the complexity and taking my example of the translation table, how is this more complicated and less understandable that requiring the concept of dictionary, keys, types (here), loop, concatenation… ;) When you learn the right way early, this becomes the simple/understandable way – mozway Feb 18 '22 at 14:42
I agree with you that it is good to learn these practices early. Also, I have to correct myself and say that I find your solutions readable and understandable. I tried to provide a solution that is similar to the code in the question. The new thing was the `int()` conversion as the question was how to map the number and the string concatenation. Your answer introduced `zip()`, `join()`, and a generator. My only point is that it can get overwhelming really fast. – JANO Feb 18 '22 at 15:01

Converting an integer to a sequence of letters using a function

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