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R - Concatenate two dataframes?
...2 data frames, you can use Reduce(rbind, list_of_data_frames) to mash them all together!
– Yourpalal
Aug 13 '15 at 21:12
1
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Effect of NOLOCK hint in SELECT statements
...l complete faster than a normal select.
2) Yes, a select with NOLOCK will allow other queries against the effected table to complete faster than a normal select.
Why would this be?
NOLOCK typically (depending on your DB engine) means give me your data, and I don't care what state it is in, and d...
Big O of JavaScript arrays
...pending - Amortized O(1) (sometimes resizing the hashtable is required; usually only insertion is required)
Prepending - O(n) via unshift, since it requires reassigning all the indexes
Insertion - Amortized O(1) if the value does not exist. O(n) if you want to shift existing values (Eg, using splice...
How can I remove an element from a list, with lodash?
...eturn an element if the predicate is true. Your implementation will return all unwanted elements instead of those you want to keep
– Xeltor
Jun 14 '17 at 19:26
5
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Abstract methods in Python [duplicate]
...what a metaclass is, don't worry about it. :-)
– kindall
Dec 8 '10 at 0:15
1
The linked tutorial ...
How do you generate dynamic (parameterized) unit tests in python?
...
This is called "parametrization".
There are several tools that support this approach. E.g.:
pytest's decorator
parameterized
The resulting code looks like this:
from parameterized import parameterized
class TestSequence(unittes...
What's the difference between ISO 8601 and RFC 3339 Date Formats?
...the web. Should I use one over the other? Is one just an extension? Do I really need to care that bad?
3 Answers
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How to use filter, map, and reduce in Python 3
... longer return lists:
[...]
map() and filter() return iterators. If you really need a list, a quick fix is e.g. list(map(...)), but a better fix is often to use a list comprehension (especially when the original code uses lambda), or rewriting the code so it doesn’t need a list at all. Particular...
jQuery selector for the label of a checkbox
...browsers (Safari/Chrome), you can do $('#comedyclubs')[0].labels to access all the labels assigned to #comedyclubs.
– Matt
Aug 9 '12 at 2:17
1
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Shell equality operators (=, ==, -eq)
...nd many other shells) adopted. That's the whole point -- if you have [[ at all, then you can safely assume that all the extensions ksh implemented around it (fnmatch()-style pattern matching, ERE regular expressions with =~, and yes, suppression of string-splitting and filesystem globbing) will be a...