random.randrange

[ravioli2929]

I need to use the random.randrange function to randomly select a character from a string the string is the alphabet. I cant use random choice

[DeaD_EyE]

import string

print(string.ascii_letters)
# index access
print(string.ascii_letters[0])
n_letters = len(string.ascii_letters)
index = random.randrange(0, n_letters + 1)
# read the documentation about randint and randrange to understand the difference

I think you'll find out the rest.

[ravioli2929]

import random
alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmopqrstuvwxyz"
random_characters = len(alphabet)
index = random.randrange(0, random_characters + 1)
print(index)

I'm a bit confused. I have to use the variable alphabet(I'm new to python 1 week in)

[perfringo]

Maybe I am missing something but from documentation: random.randrange

random.randrange(stop)
/../
Return a randomly selected element from range(start, stop, step).

Why random.randrange(0, random_characters + 1) and not justrandom.randrange(len(alphabet)). Latter will give random number which is in range of valid indexes:

>>> a = [1, 2, 3]
>>> len(a)
2
>>> max(random.randrange(0, len(a) + 1) for x in range(100))
3
>>> max(random.randrange(len(a)) for x in range(100))
2
>>> a[3]
Index Error
/../

[ravioli2929]

i need the specfic letter for example 0 will be A.
I need the output to show A

[perfringo]

I think that I do understand. Just if you have random.randrange(0, len(alphabet) + 1) then:

>>> alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmopqrstuvwxyz"
>>> len(alphabet)
51
>>> max(random.randrange(0, len(alphabet) + 1) for x in range(1000))
51
>>> alphabet[51]
Index Error
/../
IndexError: string index out of range

This means that random.randrange can return you index which is out of range.

Regarding conditions: must all letters be unique or can there be duplicates?

[ravioli2929]

there can be duplicates
unfortunately i cant use the for or in functions as it is homework.

[DeaD_EyE]

Don't make your own alphabet string.
You have forgotten the n.

import string
print(string.ascii_letters)

The IndexError is raised, because you try to access the 51th element, but the indexing starts with 0.
This means, if you have 51 elements/letters, the last letter in this list is at index 50. The first letter is at index 0.

You need to learn more about slicing: https://stackoverflow.com/questions/5092...e-notation

Read the documentation about randrange and randint.
For randrange you can use the output from len. With randint the stop value is inclusive. This means it is len(your_strig) + 1.

[snippsat]

Your nearly there in your code post #3
Just add alphabet[index]

import random

alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmopqrstuvwxyz"
random_characters = len(alphabet)
index = random.randrange(0, random_characters + 1)
print(index)
print(alphabet[index])

A little fancier output

import random

alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmopqrstuvwxyz"
random_characters = len(alphabet)
index = random.randrange(0, random_characters + 1)
print(f'Random characters at index <{index}> give output <{alphabet[index]}>')

Output:
Random characters at index <3> has result of <D>
Random characters at index <1> give output <B>
Random characters at index <24> give output <Y>

[ravioli2929]

thanks for the help guys relatively new to this. Just asking how would I ask for more than one value say I
wanted 6 different random letters (there can be a duplicate)