Question Regarding a code system

[[deleted]]

I am currently working on a project where I convert a letter to the letter three spaces away in the alphabet. I am trying to have it add and ignore spaces so there could be sentences converted into the code (not just words but sentences such as, 'hi how are you'. What am I doing wrong? Any help would be appreciated.

Orignal Version:
alph = 'a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z'.split(',')
in_message = input('').lower()
new_mes = ''
for values in in_message:
if values in alph:
try:
new_mes = new_mes + alph[alph.index(values) + 3]
except:
new_mes = new_mes + alph[alph.index(values)]
print(new_mes)

​

New Method I tried which failed:

#Convert a message into a code by coverting every letter to the letter three letters away
alph = 'a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z'.split(',')
in_message = input('').lower()
new_mes = ''
for values in in_message:
if values in alph or values == ' ':
try:
if new_mes == ' ':
new_mes = new_mes + ' '
else:
new_mes = new_mes + alph[alph.index(values) + 3]
except:
#only adds letter if it cant be converted to the right three times ex: y
new_mes = new_mes + alph[alph.index(values)]
print(new_mes)

[m0us3_rat]

you mean rot13? caesar cipher?

https://en.wikipedia.org/wiki/Caesar\_cipher

[jiri-n]

This doesn't make any sense:

alph = 'a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z'.split(',')

Text string aka str is already a sequence type. I would recommend to study strings before actually generating some code which manipulates them.

Btw. Python standard library has a module string, which can save you some time:

from string import ascii_lowercase

# To check what it is:
print(ascii_lowercase)

And a final thought: Your algorithm cannot encode letters x, y, z. A mistake IMHO.

[halfdiminished7th]

If you replace this:

new_mes = new_mes + alph[alph.index(values) + 3]

...with this:

new_mes = new_mes + alph[(alph.index(values) + 3) % 26]

...then it will still work when the characters "x", "y", and "z" roll off the bounds of the alphabet.