All Questions
13 questions
1
vote
3
answers
52
views
Iteration Functionality
Below is the simple programme which I wrote in Python
Animal = ['tiger','lion','dog','cat']
xyz = iter(Animal)
print(next(xyz))
The output was
tiger
Now I read that iter() method points towards the ...
- 45
1
vote
1
answer
59
views
For loop creates only one array instead of multiple
I have binary images containing different numbers of objects and I have to count the number of spots (the coordinates of these spots come from csv files) inside each object.
The code I have works when ...
0
votes
0
answers
269
views
Implementing the range object as an iterator using generator function
I'm new to Python and I am trying to implement the range() object with positive step values as an iterator using a generator function in Python. I have already implemented this iterator by defining a ...
1
vote
1
answer
303
views
Why not make all iterables their own multiple pass iterators?
I'm new to Python, but my understanding of iterables and iterators in Python is that they support the iterator protocol.
In some iteration tool/context, an iterable is passed to iter() to return an ...
- 121
0
votes
2
answers
44
views
Why is a variable not getting assigned to when assignments exist in both clauses of an if-else block?
Suppose we have something like:
if True:
r = 0
else:
r = 1
print(r)
Why would we get UnboundLocalError: local variable 'r' referenced before assignment?
The actual code is shown below:...
- 4,670
0
votes
3
answers
34
views
How to define two ways of iterate according input
What is the most pythonic form to define two ways of iterating. In example, I have this original code:
def f1(cat_gen):
for (a, b), c in cat_gen:
if some condition:
yield (a, ...
- 2,101
1
vote
1
answer
661
views
How do I iterate through two lists in API call Python 3
I have two files containing information that I need to input in the same script. One containing ID's, one on each line, and the other list containing parameters on their own individual lines as well. ...
1
vote
0
answers
49
views
Python3.6: Use import os, iter and next to print directory of files with the same extension
Python 3.6
import os
files = os.open('dir *.py')
file_iter = iter(files)
print(next(file_iter))
#Output: Volume in drive C is c
However when I use a for loop:
for file in files:
print((file), ...
- 11
0
votes
1
answer
3k
views
Return average / mean of a specific key in a list of dictionaries
This is probably a duplicate, so please let me know if I didn't find something.
My question is in the title.
I know that the following code would do it, but I don't think this is how it should be ...
- 2,145
2
votes
1
answer
256
views
Loop for `times` if `times is not None` else loop forever
Suppose I have a function of the form
def foo(times=None):
iterator = range(times) if times else itertools.count()
for _ in iterator:
# do stuff
Is there a more Pythonic or elegant ...
- 3,792
8
votes
1
answer
689
views
Why does map over an iterable return a one-shot iterable?
Why does map when called with an object which can be iterated over multiple times not return an object which can also be iterated multiple times? I think the latter is much more reasonable.
My use ...
- 2,489
2
votes
1
answer
464
views
Force all iterations on an iterable
I've written a for-loop using map, with a function that has a side-effect. Here's a minimal working example of what I mean:
def someFunc(t):
n, d = t
d[n] = str(n)
def main():
d = {}
...
- 114k
2
votes
1
answer
58
views
why reversed() list iteration with step doesn't work properly?
def checkio(data):
s1=[]
s2=[]
data.sort()
for x in reversed(data[0:len(data):2]):
s1.append(x)
for y in reversed(data[0:(len(data)-1):2]):
s2.append(y)
print(s1, s2)
...
- 718