Trying to create a string of bit numbers using for loop in python

Question

for i in range(len(p)):
    x = ""
    if (p[i] == "1") or (q[i] == "1"):
      x[i] = 1
    else:
      x[i] = 0

I have this so far. I basically just want to know how to concatenate onto the string x to add more bits since python strings are immutable. I barely started using python or i would explain myself better

p and q are bits so "1101" and "1001" respectively. The output should be another string of bits so "1101" for example — WeepingWillow, Sep 08 '20 at 23:18
String concatenation is demonstrated in any tutorial on Python strings. Where are you having trouble? — Prune, Sep 08 '20 at 23:21
@WeepingWillow -- hey, sorry to address you via a comment on an unrelated post, but I can't reach you otherwise since you deleted the other question so it's no longer able to be commented on. See https://gist.github.com/charles-dyfis-net/a4dc8b9c8f52c7201b0e1b1344939e55 for an example of how to shorten your logic-gate demo code. — Charles Duffy, Sep 17 '20 at 21:52

score 0 · Answer 1 · answered Sep 08 '20 at 23:19

0

This should work:

x = ""
for i in range(len(p)):
    if (p[i] == "1") or (q[i] == "1"):
      x += "1"
    else:
      x += "0"

Keep in mind I think iterating on both at the same time and using a list would be better:

x = []
for i, j in zip(p, q):
    if i == "1" or j == "1":
        x.append("1")
    else:
        x.append("0")
x = "".join(x)

answered Sep 08 '20 at 23:19

Bharel

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Okay this makes sense. I've never used zip. I basically have 0 python experience so I was using my knowledge of other languages. – WeepingWillow Sep 08 '20 at 23:29

score 0 · Answer 2 · answered Sep 08 '20 at 23:21

0

Why not just use str.join and a comprehension. Also just loop through each string simultaneously using zip:

''.join('1' if '1' in g else '0' for g in zip(p, q))

answered Sep 08 '20 at 23:21

Jab

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ibra · Accepted Answer · 2020-09-08T23:57:43.177

1- Create a list with length of P, that contain only "0" elements
2- Work with this list to change the element at the corresponding index
3- At the end, join the element of the list to get one string

p = "11100011"
q = "00000011"

list_x = ["0"]*len(p)

for i in range(len(p)):
    if (p[i] == "1") or (q[i] == "1"):
      list_x[i] = "1"

str = "".join(list_x)

print (str)

it gives you

11100011

for more details:

Changing one character in a string on stackoverflow good luck.

An important point here is the index i, this method work independently where you start the strings (from beginning or the end or at any point).
If you want to start from the beginning of the string, so you can use the solution proposed by others (@Bharel and @Jab).

x = ""
for i in range(len(p)):
    if (p[i] == "1") or (q[i] == "1"):
      x += "1"
    else:
      x += "0"

Trying to create a string of bit numbers using for loop in python

3 Answers3