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Does Java 8 provide a good way to repeat a value or function?
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edited Aug 30 '13 at 12:43
answered Aug 30 '13 at 12:08
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What is the purpose of setting a key in data.table?
...e other vignettes that we plan to.
I've updated this answer again (Feb 2016) in light of the new on= feature that allows ad-hoc joins as well. See history for earlier (outdated) answers.
What exactly does setkey(DT, a, b) do?
It does two things:
reorders the rows of the data.table DT by the...
Hashing a file in Python
... break
md5.update(data)
sha1.update(data)
print("MD5: {0}".format(md5.hexdigest()))
print("SHA1: {0}".format(sha1.hexdigest()))
What we've done is we're updating our hashes of this bad boy in 64kb chunks as we go along with hashlib's handy dandy update method. This way we use a...
iPhone UIView Animation Best Practice
...ions:context: method:
Use of this method is discouraged in iPhone OS 4.0 and later. You should use the block-based animation methods instead.
Eg of Block-based Animation based on Tom's Comment
[UIView transitionWithView:mysuperview
duration:0.75
options:U...
How do I set the time zone of MySQL?
... MySQL:
In the file "my.cnf" in the [mysqld] section
default-time-zone='+00:00'
@@global.time_zone variable
To see what value they are set to:
SELECT @@global.time_zone;
To set a value for it use either one:
SET GLOBAL time_zone = '+8:00';
SET GLOBAL time_zone = 'Europe/Helsinki';
SET @@glo...
Finding the index of an item in a list
...n give index a hint. For instance, in this snippet, l.index(999_999, 999_990, 1_000_000) is roughly five orders of magnitude faster than straight l.index(999_999), because the former only has to search 10 entries, while the latter searches a million:
>>> import timeit
>>> timeit.ti...
Changing the browser zoom level
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answered Jun 28 '09 at 17:48
Eemeli KantolaEemeli Kantola
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How to center a button within a div?
I have a div that's width is 100%.
14 Answers
14
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In PHP, how do you change the key of an array element?
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answered Oct 27 '08 at 17:12
KernelMKernelM
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In C#, how do I calculate someone's age based on a DateTime type birthday?
...Now it's much faster.
– JAG
Jan 22 '09 at 10:29
106
Given we're talking birthdays you can just us...