Check if line from a file contains an uppercase letter in Python

Question

I am reading a file line by line and let's say I don't care about anything except "if" this line of the file contains an upper case letter. Because if it does I want to use it. I don't want to use the this line of the file if it does not.

Could I use just an if statement for this? or do I have to use a for loop. I already have two nested statements.

My code:

with open(var) as config_file: #open file
for line in config_file: #line by line reading of file
    #if "description" and capital letter is contain in line:
        line = line.replace('\n' , '').replace('"' , '').replace(']' , '') #removes all extra characters
        i = "| except " + (line.split("description ", 1)[1]) + " " #split the line and save last index (cust name)
        cus_str+=i #append to string
config_file.close()

can u share a sample from your file ? – Inder Jul 13 '18 at 17:07 — Inder, Jul 13 '18 at 17:07

score 5 · Answer 1 · answered Jul 13 '18 at 17:08

5

Yes. The built-in any function makes this simple:

with open(filename) as f:
    for line in f:
        if any(letter.isupper() for letter in line):
            print(line)

answered Jul 13 '18 at 17:08

Patrick Haugh

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To add on to Patrick's answer, you could also have used `if any(letter in string.ascii_uppercase for letter in line):`, assuming the `string` module has been imported and you're more comfortable with that. – Joel Jul 13 '18 at 17:21
Thank you so much! follow up question because I have some strange cases. After the substring "description_" of the line, if the next *letter* found after that is uppercase...print this line. How would I do that? – Camille Burke Jul 13 '18 at 17:36
That's probably easiest to express as a regular expression `re.search(r"description_[A-Z]", line)` – Patrick Haugh Jul 13 '18 at 17:38

score 1 · Answer 2 · answered Jul 13 '18 at 17:16

1

A regular expression is probably overkill for this, but it's extremely simple:

import re
if re.search('[A-Z]', line):

answered Jul 13 '18 at 17:16

Mark Ransom

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lenik · Answer 3 · 2018-07-13T17:19:13.357

-1

with open(var) as config_file :
    data = [i.strip() for i in config_file.readlines() if any(j != j.lower() for j in i)]

data will contain only strings with uppercase characters.

edited Jul 13 '18 at 17:19

answered Jul 13 '18 at 17:10

lenik

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This does not do what OP asked. They want to know which lines contain an uppercase, not remove them. – Josh J Jul 13 '18 at 17:12
@JoshJ thanks for the correction, missed that part, fixed now. – lenik Jul 13 '18 at 17:19

Check if line from a file contains an uppercase letter in Python

3 Answers3