Augmented assignment (or compound assignment) is the name given to certain assignment operators in certain programming languages (especially those derived from C). An augmented assignment is generally used to replace a statement where an operator takes a variable as one of its arguments and then assigns the result back to the same variable. A simple example is x += 1 which is expanded to x = x + 1.
Questions tagged [augmented-assignment]
41 questions
0
votes
2 answers
UnboundLocalError when using += on list. Why is `nonlocal` needed here when directly calling __iadd__ works fine?
Consider this code:
def main():
l = []
def func():
l += [1]
func()
print(l)
if __name__ == '__main__':
main()
It will produce:
Traceback (most recent call last):
File…
tahsmith
- 1,643
- 1
- 17
- 23
0
votes
0 answers
Function parameter is reference?
def add_list(p):
p = p + [1]
p1 = [1, 2, 3]
add_list(p1)
print p1
res:[1, 2, 3]
BUT
def add_list(p):
p += [1]
p1 = [1, 2, 3]
add_list(p1)
print p1
res:[1, 2, 3, 1]
I don't know why, can someone explain this? What's the main difference…
kker neo
- 133
- 4
0
votes
2 answers
Python ternary conditional for joining string
Answered by Martijn Pieters. Thank you.
It is because statement vs expression.
And because .join() does not mutate (is a pure function), so it needs to be assigned to a variable.
Question:
What is the reason for this oddity?
Goal:
if base == 'T':
…
Luigi
- 45
- 1
- 8
0
votes
2 answers
Augmented assignment in the middle of expression causes SyntaxError
In my code I have these lines:
if numVotes == 0:
avId in self.disconnectedAvIds or self.resultsStr += curStr
When I run the code I get this error?
SyntaxError: illegal expression for augmented assignment
How do I fix this error?
Zach Gates
- 4,045
- 1
- 27
- 51
0
votes
0 answers
How does Fortran handle augmented assignment of arrays?
I've been working on some code lately that requires me to shift elements in an array left, right, up, and down (depending on an index i). My first thought was to try something like this:
subroutine shift(f)
real, intent(inout) :: f(0:8, rDim,…
rayhem
- 741
- 1
- 8
- 23
0
votes
1 answer
android augmented reality image targets
I am planning to develop an augmented reality application for Android phone. Does anyone know if there is any existing framework(in java programming langueage) for augmented reality which could be used for such applications?
Thanks.
user3345767
- 349
- 1
- 2
- 11
0
votes
0 answers
Why is it that Lua doesn't have augmented assignment?
Please note that this is a genuine question. I'm not rep-whoring. But if anyone feels like closing it like this one please don't close before I get an answer.
That said, I'd seriously like to know why Lua doesn't have augmented assignment like most…
Plakhoy
- 1,846
- 1
- 18
- 30
-1
votes
2 answers
Is this code thread-safe in python 2.7?
Should I use atomic counter with Locking or can I use this?
def somefunc(someparam):
if someparam:
dic['key'] +=1
oshaiken
- 2,593
- 1
- 15
- 25
-2
votes
1 answer
Python operator precedence with augmented assignment including sequence
Following up my previous question I have the following one. Are these the same in Python?
a += b[1] / 2
and
a += (b[1] / 2)
Providing that:
a has already been defined earlier as float
b is a list of tuples
b[1] is a tuple with a single…
Manngo
- 829
- 7
- 24
-2
votes
3 answers
Why does the original list change?
Running this:
a = [[1], [2]]
for i in a:
i *= 2
print(a)
Gives
[[1, 1], [2, 2]]
I would expect to get the original list, as happens here:
a = [1, 2]
for i in a:
i *= 2
print(a)
Which gives:
[1, 2]
Why is the list in the first example…
blueFast
- 41,341
- 63
- 198
- 344
-3
votes
1 answer
python augmented assignment statements, display the results as per the output
Write a program which asks the user to enter an integer and then by using augmented assignment statements, display the results as per the output
Please enter the first integer: 5
Please enter the second integer: 4
5 + 4 is 9
5 - 4 is 1
5 * 4 is 20
5…
goldie
- 1
- 1