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How do you create nested dict in Python?
...t;> d
{'dict1': {'innerkey': 'value'}}
You can also use a defaultdict from the collections package to facilitate creating nested dictionaries.
>>> import collections
>>> d = collections.defaultdict(dict)
>>> d['dict1']['innerkey'] = 'value'
>>> d # currentl...
Run certain code every n seconds [duplicate]
...eneralization of Alex Martelli's answer, with start() and stop() control:
from threading import Timer
class RepeatedTimer(object):
def __init__(self, interval, function, *args, **kwargs):
self._timer = None
self.interval = interval
self.function = function
...
How to convert a string into double and vice versa?
...and, while others will write "1,000" and others "1.000" - which do you get from -[NSString doubleValue]?
– Chris Hanson
Oct 4 '08 at 19:06
9
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Using LINQ to remove elements from a List
...would just change the value of authorsList instead of removing the authors from the previous collection. Alternatively, you can use RemoveAll:
authorsList.RemoveAll(x => x.FirstName == "Bob");
If you really need to do it based on another collection, I'd use a HashSet, RemoveAll and Contains:
...
Best algorithm for detecting cycles in a directed graph [closed]
...
has the pseudo-code for one algorithm, and a brief description of another from Tarjan. Both have O(|V| + |E|) time complexity.
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Can I update a component's props in React.js?
... with React.js, it seems like props are intended to be static (passed in from the parent component), while state changes based upon events. However, I noticed in the docs a reference to componentWillReceiveProps , which specifically includes this example:
...
How to percent-encode URL parameters in Python?
...
Python 2
From the docs:
urllib.quote(string[, safe])
Replace special characters in string
using the %xx escape. Letters, digits,
and the characters '_.-' are never
quoted. By default, this function is
intended for quotin...
Converting JSON String to Dictionary Not List
...nts, and then adding [0] on the end of it will take just the first element from that resulting list slice. What you need to use to get the result you want is a list comprehension:
[p[0] for p in datapoints[0:5]]
Here's a simple way to calculate the mean:
sum(p[0] for p in datapoints[0:5])/5. # R...
In Python, how do you convert a `datetime` object to seconds?
...
Consider using: datetime.datetime.utcfromtimestamp(0) I've used this to get the 'epoch' easily. Note that epoch is not always the same on all systems.
– D. A.
Nov 5 '13 at 20:04
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How to split a string in shell and get the last field
...ng operators:
$ foo=1:2:3:4:5
$ echo ${foo##*:}
5
This trims everything from the front until a ':', greedily.
${foo <-- from variable foo
## <-- greedy front trim
* <-- matches anything
: <-- until the last ':'
}
...