Linked Questions
121 questions linked to/from What is the EAFP principle in Python?
0
votes
1
answer
60
views
Which one is better to use in this example? Try-Except or If-Else? [duplicate]
I have just read some questions about when to use exception handling. And a question came up, from these 2, which one is better?
def get_ans(q):
while True:
x = input(q)
if x.isdigit():
...
- 11
4481
votes
47
answers
6.7m
views
How can I find the index for a given item in a list?
Given a list ["foo", "bar", "baz"] and an item in the list "bar", how do I get its index 1?
- 49.2k
343
votes
35
answers
416k
views
What is the pythonic way to detect the last element in a 'for' loop?
How can I treat the last element of the input specially, when iterating with a for loop? In particular, if there is code that should only occur "between" elements (and not "after" ...
- 5,367
381
votes
21
answers
1.1m
views
"for line in..." results in UnicodeDecodeError: 'utf-8' codec can't decode byte
Here is my code,
for line in open('u.item'):
# Read each line
Whenever I run this code it gives the following error:
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xe9 in position 2892: ...
- 11.5k
339
votes
25
answers
386k
views
How to read a single character from the user?
Is there a way of reading one single character from the user input? For instance, they press one key at the terminal and it is returned (sort of like getch()). I know there's a function in Windows for ...
- 102k
205
votes
11
answers
469k
views
If list index exists, do X [duplicate]
I need to code such that if a certain list index exists, then run a function.
My failing code:
n = int(input("Define number of actors: "))
count = 0
nams = []
while count < n:
count = ...
- 2,495
155
votes
8
answers
26k
views
How do "and" and "or" act with non-boolean values?
I'm trying to learn python and came across some code that is nice and short but doesn't totally make sense
the context was:
def fn(*args):
return len(args) and max(args)-min(args)
I get what it'...
- 2,019
202
votes
3
answers
159k
views
Conditional import of modules in Python [duplicate]
In my program I want to import simplejson or json based on OS being Linux or Windows. I take the OS name as input from the user. Now, is it correct to do it with a condition like this?
osys = ...
- 2,061
83
votes
6
answers
128k
views
How to overwrite a folder if it already exists when creating it with makedirs?
The following code allows me to create a directory if it does not already exist.
dir = 'path_to_my_folder'
if not os.path.exists(dir):
os.makedirs(dir)
The folder will be used by a program to ...
- 2,367
39
votes
8
answers
81k
views
Upload files using SFTP in Python, but create directories if path doesn't exist
I want to upload a file on a remote server with Python. I'd like to check beforehand if the remote path is really existing, and if it isn't, to create it. In pseudocode:
if(remote_path not exist):
...
- 5,923
25
votes
10
answers
35k
views
Python, Determine if a string should be converted into Int or Float
I want to convert a string to the tightest possible datatype: int or float.
I have two strings:
value1="0.80" #this needs to be a float
value2="1.00" #this needs to be an integer.
How I can ...
- 1,551
29
votes
12
answers
26k
views
Python list.index throws exception when index not found
Why does list.index throw an exception, instead of using an arbitrary value (for example, -1)? What's the idea behind this?
To me it looks cleaner to deal with special values, rather than exceptions.
...
- 334k
29
votes
1
answer
32k
views
Python Get Property if Object is not None
Is there a Pythonic way to grab a property if an object exists on one line of code? Currently in the code below if someone passes in a None type object the code will break, so I need some clean way to ...
- 1,219
13
votes
4
answers
32k
views
What's the best way to check if class instance variable is set in Python?
I have a variable which may or may not get a value in the instance:
class EC():
__init__(self, a=False):
...
if a: self.__var = ...
Later I want to check if the __var exists in the instance. ...
- 821
12
votes
3
answers
31k
views
Simple DER Cert Parsing in python
Which is the best way to parse with python a binary file with X509 Certificate in DER format to extract public key.
- 821