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Set environment variables on Mac OS X Lion
...ble you set in your .bash_profile will only affect your bash shells.
Generally I only set variables in my .bash_profile file and don't change the .plist file (or launchd file on Mavericks). Most OS X windowed applications don't need any custom environment. Only when an application actually needs a ...
Difference between len() and .__len__()?
Is there any difference between calling len([1,2,3]) or [1,2,3].__len__() ?
4 Answers
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Can you create nested WITH clauses for Common Table Expressions?
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Essentially the post means, that you can't do it, but it is not a big problem.
– peterh - Reinstate Monica
May 30 '17 at 14:40
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How to overcome TypeError: unhashable type: 'list'
...used to compare dictionary keys during a dictionary lookup quickly.
Internally, hash() method calls __hash__() method of an object which are set by default for any object.
Converting a nested list to a set
>>> a = [1,2,3,4,[5,6,7],8,9]
>>> set(a)
Traceback (most recent call last...
How do I get a UTC Timestamp in JavaScript?
While writing a web application, it makes sense to store (server side) all datetimes in the DB as UTC timestamps.
16 Answ...
How can I transform between the two styles of public key format, one “BEGIN RSA PUBLIC KEY”, the oth
...s of two numbers:
the modulus (e.g. a 2,048 bit number)
the exponent (usually 65,537)
Using your RSA public key as an example, the two numbers are:
Modulus: 297,056,429,939,040,947,991,047,334,197,581,225,628,107,021,573,849,359,042,679,698,093,131,908,015,712,695,688,944,173,317,630,555,849,7...
Counting inversions in an array
...m to do the following: Given array A[1... n] , for every i < j , find all inversion pairs such that A[i] > A[j] . I'm using merge sort and copying array A to array B and then comparing the two arrays, but I'm having a difficult time seeing how I can use this to find the number of inversions...
Is it possible to have multiple statements in a python lambda expression?
...Q. Can you put multiple statements in a lambda?
A. No. But you don't actually need to use a lambda. You can put the statements in a def instead. i.e.:
def second_lowest(l):
l.sort()
return l[1]
map(second_lowest, lst)
Q. Can you get the second lowest item from a lambda by sorting the ...
$_POST vs. $_SERVER['REQUEST_METHOD'] == 'POST'
Some guy called one of my Snipplr submissions "crap" because I used if ($_SERVER['REQUEST_METHOD'] == 'POST') instead of if ($_POST)
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Anonymous recursive PHP functions
... pass it by reference. Be aware, that if you modify the $factorial before calling the function, the result will change as it's passed by reference.
– Marius Balčytis
Sep 13 '12 at 21:48
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