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Mongoose indexing in production code
...dex in production. Once the index has been added, subsequent ensureIndex calls will simply see that the index already exists and then return. So it only has an effect on performance when you're first creating the index, and at that time the collections are often empty so creating an index would be...
history.replaceState() example?
...ight be to keep using replaceState() and simply set the document title manually document.title = "title"
– newshorts
Nov 7 '16 at 18:49
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Reverse colormap in matplotlib
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The standard colormaps also all have reversed versions. They have the same names with _r tacked on to the end. (Documentation here.)
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Common use-cases for pickle in Python
...hon data over a TCP connection in a multi-core or distributed system (marshalling)
3) storing python objects in a database
4) converting an arbitrary python object to a string so that it can be used as a dictionary key (e.g. for caching & memoization).
There are some issues with the last one ...
Best algorithm for detecting cycles in a directed graph [closed]
What is the most efficient algorithm for detecting all cycles within a directed graph?
14 Answers
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Transaction isolation levels relation with locks on table
...B just executes a SELECT statement to read data. C reads and updates data. All these process work on the same table T.
READ UNCOMMITTED - no lock on the table. You can read data in the table while writing on it. This means A writes data (uncommitted) and B can read this uncommitted data and use it...
C++ preprocessor __VA_ARGS__ number of arguments
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This is actually compiler dependent, and not supported by any standard.
Here however you have a macro implementation that does the count:
#define PP_NARG(...) \
PP_NARG_(__VA_ARGS__,PP_RSEQ_N())
#define PP_NARG_(...) \
...
Explicitly calling return in a function or not
...ek from the R core team (I believe) for recommending a user to explicitly calling return at the end of a function (his comment was deleted though):
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How to assert output with nosetest/unittest in python?
...rarily replacing sys.stdout. I prefer the context manager because it wraps all the bookkeeping into a single function, so I don't have to re-write any try-finally code, and I don't have to write setup and teardown functions just for this.
import sys
from contextlib import contextmanager
from String...
How can I correctly prefix a word with “a” and “an”?
...uick filter program that spits out only article text (the download is generally in XML format, along with non-article metadata too).
Find all instances of a(n).... and make an index on the following word and all of its prefixes (you can use a simple suffixtrie for this). This should be case sensitiv...