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Is it safe to remove selected keys from map within a range loop?
How can one remove selected keys from a map?
Is it safe to combine delete() with range, as in the code below?
4 Answers
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MySQL INNER JOIN select only one row from second table
I have a users table and a payments table, for each user, those of which have payments, may have multiple associated payments in the payments table. I would like to select all users who have payments, but only select their latest payment. I'm trying this SQL but i've never tried nested SQL sta...
Which are more performant, CTE or temporary tables?
Which are more performant, CTE or Temporary Tables ?
12 Answers
12
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e.printStackTrace equivalent in python
...ow that print(e) (where e is an Exception) prints the occurred exception
but, I was trying to find the python equivalent of Java's e.printStackTrace() that exactly traces the exception to what line it occurred and prints the entire trace of it.
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__proto__ VS. prototype in JavaScript
What are the differences between __proto__ and prototype ?
30 Answers
30
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What does the star operator mean, in a function call?
...ence/collection into positional arguments, so you can do this:
def sum(a, b):
return a + b
values = (1, 2)
s = sum(*values)
This will unpack the tuple so that it actually executes as:
s = sum(1, 2)
The double star ** does the same, only using a dictionary and thus named arguments:
value...
What's the difference between INNER JOIN, LEFT JOIN, RIGHT JOIN and FULL JOIN? [duplicate]
What's the difference between INNER JOIN , LEFT JOIN , RIGHT JOIN and FULL JOIN
in MySQL ?
3 Answers
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Splitting on last delimiter in Python string?
...u specify how many times to split, while str.rpartition() only splits once but always returns a fixed number of elements (prefix, delimiter & postfix) and is faster for the single split case.
Demo:
>>> s = "a,b,c,d"
>>> s.rsplit(',', 1)
['a,b,c', 'd']
>>> s.rsplit(',...
Map function in MATLAB?
I'm a little surprised that MATLAB doesn't have a Map function, so I hacked one together myself since it's something I can't live without. Is there a better version out there? Is there a somewhat-standard functional programming library for MATLAB out there that I'm missing?
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Changing iframe src with Javascript
... trying to change an <iframe src=... > when someone clicks a radio button. For some reason my code is not working correctly and I am having trouble figuring out why. Here is what I have:
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