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Is there any pythonic way to combine two dicts (adding values for keys that appear in both)?
...rom collections import Counter
>>> A = Counter({'a':1, 'b':2, 'c':3})
>>> B = Counter({'b':3, 'c':4, 'd':5})
>>> A + B
Counter({'c': 7, 'b': 5, 'd': 5, 'a': 1})
Counters are basically a subclass of dict, so you can still do everything else with them you'd normally do wit...
kill -3 to get java thread dump
I am using kill -3 command to see the JVM's thread dump in unix. But where can I find the output of this kill command? I am lost!!
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Most efficient way to prepend a value to an array
...-O but certainly using the unshift method is more concise:
var a = [1, 2, 3, 4];
a.unshift(0);
a; // => [0, 1, 2, 3, 4]
[Edit]
This jsPerf benchmark shows that unshift is decently faster in at least a couple of browsers, regardless of possibly different big-O performance if you are ok with mo...
How to make the 'cut' command treat same sequental delimiters as one?
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edited Apr 23 '18 at 23:03
Austin Adams
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Elegant ways to support equivalence (“equality”) in Python classes
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342
Consider this simple problem:
class Number:
def __init__(self, number):
self.num...
Swift make method parameter mutable?
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As stated in other answers, as of Swift 3 placing var before a variable has been deprecated. Though not stated in other answers is the ability to declare an inout parameter. Think: passing in a pointer.
func reduceToZero(_ x: inout Int) {
while (x != 0) {
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What is the difference between int, Int16, Int32 and Int64?
What is the difference between int , System.Int16 , System.Int32 and System.Int64 other than their sizes?
10 Answers
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No module named _sqlite3
...ect this problem with the steps below:
Install sqlite-devel (or libsqlite3-dev on some Debian-based systems)
Re-configure and re-compiled Python with ./configure --enable-loadable-sqlite-extensions && make && sudo make install
Note
The sudo make install part will set that pyth...
How do I run multiple background commands in bash in a single line?
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335
Exactly how do you want them to run? If you want them to be started in the background and run ...
