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Check if a given key already exists in a dictionary
...()
for i in range(100):
key = i % 10
d[key] = d.get(key, 0) + 1
and if you wanted to always ensure a default value for any key you can either use dict.setdefault() repeatedly or defaultdict from the collections module, like so:
from collections import defaultdict
d = defaultdict(int)
f...
Add disabled attribute to input element using Javascript
I have an input box and I want it to be disabled and at the same time hide it to avoid problems when porting my form.
7 Ans...
How to put a line comment for a multi-line command [duplicate]
I know how to write a multi-line command in a Bash script, but how can I add a comment for each line in a multiline command?
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LD_LIBRARY_PATH vs LIBRARY_PATH
I'm building a simple C++ program and I want to temporarily substitute a system supplied shared library with a more recent version of it, for development and testing.
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Time complexity of Euclid's Algorithm
...ow what happens over two iterations:
a', b' := a % b, b % (a % b)
Now a and b will both decrease, instead of only one, which makes the analysis easier. You can divide it into cases:
Tiny A: 2a <= b
Tiny B: 2b <= a
Small A: 2a > b but a < b
Small B: 2b > a but b < a
Equal: a ==...
Split delimited strings in a column and insert as new rows [duplicate]
...parate_rows function as described by @Tif below.
It works so much better, and it allows to "unnest" multiple columns in a single statement:
> head(mydf)
geneid chrom start end strand length gene_count
ENSG00000223972.5 chr1;chr1;chr1;chr1;chr1;chr1;chr1;chr1;chr1 11869;1...
How do I get the calling method name and type using reflection? [duplicate]
I'd like to write a method which obtains the name of the calling method, and the name of the class containing the calling method.
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Remove CSS class from element with JavaScript (no jQuery) [duplicate]
...cript only?
Please do not give me an answer with jQuery as I can't use it, and I don't know anything about it.
13 Answers
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How to iterate through range of Dates in Java?
...t I need to perform a set of actions through range of dates, given a start and end date.
Please provide me guidance to achieve this using Java.
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Cannot ping AWS EC2 instance
...cho Request", I got confused by this for a moment.
– Andy
Jul 10 '18 at 15:23
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