How to count frequencys in python? [closed] - python

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I had a file called 'words.txt' which contains things such as. #+=%£%= and i need to go through and count each symbol without allowing any duplicates and then print my answer. for example it should look like this when printed:
# : 1
+ : 1
= : 2
% : 2
£ : 1
I know I need to use a for loop in this and that I need to use a set so It doesnt't allow any duplicates but how would I do it? Thanl you

A set isn't so useful here as it doesn't have a place to store the counts
from collections import Counter
with open("words.txt") as fin:
c = Counter(fin.read())
for item in c.items():
print("{} : {}".format(*item))

Use python dictionary:
symbols = {}
for c in string:
if c not in symbols:
symbols[c] = 0
symbols[c] += 1

Look up dictionary.
Don't want to post more as it would only spoil the exercise.

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convert multiple columns vertical text to horizontal [closed]

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I tried these, but its only for one column.
using notepad++ and python. Any solution that can do for multiple columns of text?
# Input:
tim
oso
d n
a d
y a
y
# Output:
today
is
monday
You can do this fairly easily with a loop, something like:
s = "tim\noso\nd n\na d\ny a\n y"
bits = s.split('\n')
lines = ['' for i in range(0, len(bits[0]))]
for bit in bits:
for i in range(0, len(bit)):
if bit[i] != ' ':
lines[i] += bit[i]
'\n'.join(lines)

Put a set of characters into list in python [closed]

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Essentially I want to put characters inside a list so I can make the for loop work.
Example characters (supposedly listed individually vertically. not like this showing as one line)
N/A
N/A
None
Test
Dev
I want to put these characters into a list like below
a = [N/A, N/A, None, Test, Dev]
Reason is when I use for loop into these characters (let's say there are all inside "test_report". For loop is not working because it is reading the "test_report" as like this:
N
/
A
N
/
A
N
o
n
e
count = 0
for i in test_report:
if i == "Test":
count += 1
return count
Try this...
with open('test_report.txt', 'r') as f:
test_arr = f.read().split()
print(test_arr)
Considered your test_report.txt like this...
N/A
N/A
None
Test
Dev

Compare one item of a dictionary to another item in a dictionary one by one [closed]

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Currently I'm working on an assignment where I have to compare an answer key(dictionary) to answers from students(dictionary). I have to count how many of the students answers match the answer key and return that value. I realize my current code is comparing one whole dictionary to the other and if they're all equal then it will return a value but if not it returns 0. I'm just not sure how to fix it so it returns the number of ones that match.
This is my current code. Here is the previous function forgot to add it.
def index_responses(responses):
results = {}
count = 1
for answer in responses:
"""
makes a dictionary containing the responses of the student
and mapping it to a key of Q" " depending on wht number question it is.
"""
results["Q" + str(count)] = answer[0]
count += 1
return results
Assuming the keys (here, prompt) of both dictionaries are the same, or at least for every key in the answers dictionary, there is a matching response prompt, then you can count them like so
count = 0
for prompt, response in responses.items():
if response == answers.get(prompt, None):
count += 1
return count

How to read data without specific symbol in python? [closed]

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My dataset looks like following. I am trying to read numbers in "per" column without reading "%" symbol.Being a beginner in python,I was wondering if we can do such in python. Also, if you could provide the explanation that will be great!
State Year per
A 1990 6.10%
A 1989 4.50%
B 1990 3.4%
B 1989 1.25%
Thanks in advance,
In case it is a csv file, this should help (or there might be another way to get a dataframe):
import pandas as pd
data = pd.read_csv("somefile.csv")
data["per"] = data["per"].str.replace("%", "").to_numeric()
Your file type doesn't matter for this and no modules required. It works by taking each row and going to the last word. Then it splits the percentage and removes the percent symbol.
def readFile(filename):
percents = []
with open (filename,"r") as f:
for row in f:#for each line, we remove the first one late
splitRow = row.split()[-1]# spliting the elements by word, we want the last one only
percent = splitRow
percent = percent.split("%")[0]#removing the percent
percents.append(percent)#if you want it as an number instead of a string do percents.append(float(percent))
percents = percents[1:] # removes the header "per"
return percents

Please help me clean up my function [closed]

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Here is my function's objective:
Define a procedure, find_last, that takes as input two strings, a
search string and a target string,and returns the last position in the
search string where the target string appears, or -1 if there are no
occurrences.
Here is a link to the question.
And here's my function so far:
def find_last(target, search):
find = target.find(search, 0)
if find != -1:
targets = target.find(search, find)
while targets != -1:
find = find + 1
targets = target.find(search, find)
return find - 1
else:
return -1
The code returns the answer I'm looking for with return find - 1, but I know there is a better way to go about doing this.
Any help would be greatly appreciated!
You basically implemented target.rfind(search).
Why dont you use rfind ?
>>> d = "ball foo ball"
>>> f = "ball"
>>> d.rfind(f)
12
So your method becomes a 1 liner :)
def find_last(target, search):
return target.rfind(search)
You can return target.rfind(search) and in the calling method check for -1 and handle appropriately.
Can't resist to quote this awesome piece from XKCD

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