How to find a substring in a text file using python? [duplicate] - python

This question already has answers here:
Python: find string in file
(2 answers)
Closed 2 months ago.
By using python I need to know how to find a substring in a text file.
I tried using in and not in function in python to find a substring from a text file but i am not clear about it

Finding the index of the string in the text file using readline() In this method, we are using the readline() function, and checking with the find() function, this method returns -1 if the value is not found and if found it returns 0.

finding the index of the string in the text file using readline()In this method,we are using the readline()function,and checking with the find()function,this method returns-1 if the values is not found and if found it returns o

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findall string that starts with letter "CU" and return full string [duplicate]

This question already has answers here:
pandas select from Dataframe using startswith
(5 answers)
Closed 3 years ago.
It seems like straight forward thing however could not find appropriate SO answer.
I have a column called title which contain strings. I want to find out rows that starts with letter "CU".
I've tried using df.loc however It's giving me indexError,
Using regex, re.findall(r'^CU', string)
returns 'CU' instead of full name ex: 'CU abcd'. How can I get full name that starts with 'CU'?
EDIT: SORRY, I did not notice it was a duplicate question, problem solved by reading duplicate question.
You can try:
string.startswith("CU")

make str.contains more explicit [duplicate]

This question already has answers here:
How to match a whole word with a regular expression?
(4 answers)
Closed 3 years ago.
I'm looking for a cell in a data frame that contains the word "Scan". Unfortunately, there is also a word "Scan-Steuerung" which I would like to ignore.
How can I do this in python?
Is it also possible to get the index of this cell?
I'm looking for a cell in a data frame that contains the word "Scan". Unfortunately, there is also a word "Scan-Steuerung" which I would like to ignore.
How can I do this in python?
Is it also possible to get the index of this cell?
edit: I think it would be sufficient when I can read these two lines separately. At the moment, I use:
line = df[df["Name:"].str.contains("Scan")]
and when I print, I receive both lines at once.
Use Regex pattern boundaries \b
Ex:
df["Col"].str.contains(r"\bScan\b")

getting error while using count in string "BANANA" to find "ANA" as substring using str.count() inbuild function of python [duplicate]

This question already has answers here:
Python string count not working properly? [duplicate]
(2 answers)
Closed 4 years ago.
when executing the command in python
str="BANANA"
print(str.count("ANA"))
give answer as 1.
but real answer would be 2. how to solve this
It's true that this might be misleading most tutorial sites say that count returns the number of occurences in the string, it should actually say it returns the nnumber of non-overlapping occurences in the string

Detect what a python string begins with [duplicate]

This question already has answers here:
Checking whether a string starts with XXXX
(5 answers)
Closed 5 years ago.
To detect whether a python string ends with a particular substring, say ".txt", there is a convenient built-in python string method;
if file_string.endswith(".txt"):
I would like to to detect whether a python string begins with a particular substring, say "begin_like_this". I am not able find a convenient method that I can use like this;
if file_string.beginswith("begin_like_this"):
I am using Python 3.6.
You're looking for str.startswith
if file_string.startswith("begin_like_this"):

How can I convert words in [ ] to words in line? [duplicate]

This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
How to join list of strings?
I have a couple of functions in a module to run. First, I have to use read() to read strings in a document and save it as new_string and run a function. Then, I need to read a document using readlines(). After running the first function like match = clean_passage(new_string) then match contains ['/n', 'asdf', 'dfg']. Now, I need them in a line as it is shown in the original document. So, asdf dfg. How can I convet match into a thing that contains strings in a similar fashion that we get when we read a document using readlines().
So far, to do this, I had to save it and then open it using readlines(), which takes time. Is there any way to do that using a simple command? Sorry if the explanation is not clear.
try this:
to_convert = ['/n', 'asdf', 'dfg']
original_line = " ".join(to_convert)

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