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Can Python test the membership of multiple values in a list?
...o sets can sometimes be incredibly wasteful, slowing programs down by many orders of magnitude.
Here are a few benchmarks for illustration. The biggest difference comes when both container and items are relatively small. In that case, the subset approach is about an order of magnitude faster:
>...
Accessing items in an collections.OrderedDict by index
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If its an OrderedDict() you can easily access the elements by indexing by getting the tuples of (key,value) pairs as follows
>>> import collections
>>> d = collections.OrderedDict()
>>> d['foo'] = 'python'
&...
Return positions of a regex match() in Javascript?
... @OnurYıldırım - here's a jsfiddle of it working...I've tested it all the way back to IE5...works great: jsfiddle.net/6uwn1vof
– Jimbo Jonny
Mar 29 '16 at 22:34
1
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UPDATE multiple tables in MySQL using LEFT JOIN
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See the article in my blog for performance details:
Finding incomplete orders: performance of LEFT JOIN compared to NOT IN
Unfortunately, MySQL does not allow using the target table in a subquery in an UPDATE statement, that's why you'll need to stick to less efficient LEFT JOIN syntax.
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What is the best project structure for a Python application? [closed]
...l architecture of your application.
/foo
/bar
/baz
I recommend putting all of this under the "name-of-my-product" directory. So, if you're writing an application named quux, the directory that contains all this stuff is named /quux.
Another project's PYTHONPATH, then, can include /path/to/quu...
jQuery find events handlers registered with an object
..."
$.each(event, function(j, h) {
// h.handler is the function being called
});
});
Here's an example you can play with:
$(function() {
$("#el").click(function(){ alert("click"); });
$("#el").mouseover(function(){ alert("mouseover"); });
$.each($._data($("#el")[0], "events")...
Dump a mysql database to a plaintext (CSV) backup from the command line
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In MySQL itself, you can specify CSV output like:
SELECT order_id,product_name,qty
FROM orders
INTO OUTFILE '/tmp/orders.csv'
FIELDS TERMINATED BY ','
ENCLOSED BY '"'
LINES TERMINATED BY '\n'
From http://www.tech-recipes.com/rx/1475/save-mysql-query-results-into-a-text-or-csv-fil...
How can I maintain fragment state when added to the back stack?
... back stack. However, when I return to FragmentA (by pressing back), a totally new FragmentA is created and the state it was in is lost. I get the feeling I'm after the same thing as this question, but I've included a complete code sample to help root out the issue:
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git command to show all (lightweight) tags creation dates
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It's worth piping this into sort to get a chronological order, if you're into that sort of thing.
– cam8001
Nov 27 '12 at 10:23
42
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std::vector performance regression when enabling C++11
I have found an interesting performance regression in a small C++ snippet, when I enable C++11:
1 Answer
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