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Python: split a list based on a condition?
What's the best way, both aesthetically and from a performance perspective, to split a list of items into multiple lists based on a conditional? The equivalent of:
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Iterate over object keys in node.js
Since Javascript 1.7 there is an Iterator object, which allows this:
5 Answers
5
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Convert datetime to Unix timestamp and convert it back in python
...m UTC.
If you have, or can upgrade to, Python 3.3 or later, you can avoid all of these problems by just using the timestamp method instead of trying to figure out how to do it yourself. And even if you don't, you may want to consider borrowing its source code.
(And if you can wait for Python 3.4, ...
How to write a simple database engine [closed]
...ny, so I am hoping someone else can point me in the right direction. Basically, I would like information on the following:
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How to prevent buttons from submitting forms
...just plain idiotic, and a huge mistake in the spec. I use buttons in forms all the time, and even if it were an edge case (which it isn't), it'd still make sense to have the default type be submit.
– dudewad
Oct 27 '15 at 22:54
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Embedded MongoDB when running integration tests
...ed mongo for each test fails most of the tests. Its better to start before all the tests and shutdown once all have executed
– DBS
Apr 30 '19 at 5:36
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Looping over arrays, printing both index and value
...., not splitting them on whitespace. If foo=(x 'y z'), then f "${foo[@]}" calls f with two arguments, x and 'y z'. Metadata queries like "${!foo[@]}" and "${#foo[@]}" similarly act on foo as an array.
– BallpointBen
Sep 5 '18 at 1:23
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Replace non-ASCII characters with a single space
I need to replace all non-ASCII (\x00-\x7F) characters with a space. I'm surprised that this is not dead-easy in Python, unless I'm missing something. The following function simply removes all non-ASCII characters:
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Fastest way to replace NAs in a large data.table
....805 12.301 134.985
system.time(a_andrie = f_andrie(dt1))
Error: cannot allocate vector of size 305.2 Mb
Timing stopped at: 14.541 7.764 68.285
system.time(f_dowle(dt1))
user system elapsed
7.452 4.144 19.590 # EDIT has faster than this
identical(a_gdata, dt1)
[1] TRUE
Note th...
How to apply bindValue method in LIMIT clause?
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@Ross I cannot specifically answer this- but I can point out that LIMIT and OFFSET are features that were glued on AFTER all this PHP/MYSQL/PDO madness hit the dev circuit... In fact, I believe it was Lerdorf himself who oversaw LIMIT implementatio...