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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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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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How to join absolute and relative urls?
.../test1/test4/test6.xml'
With Python 3 (where urlparse is renamed to urllib.parse) you could use it as follow:
>>> import urllib.parse
>>> urllib.parse.urljoin(url1, url2)
'http://127.0.0.1/test1/test4/test6.xml'
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