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Is there an R function for finding the index of an element in a vector?
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I think it would be helpful to stress that the order of the arguments in match matters if you want the index of the first occurrence. For your example, match(x,c(4,8)) gives different results, which is not super obvious at first.
– apitsch
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The performance impact of using instanceof in Java
...y "slow" operations, including instanceof, exception handling, reflection, etc.
As Donald Knuth wrote, "We should forget about small efficiencies, say about 97% of the time: premature optimization is the root of all evil." The performance of instanceof probably won't be an issue, so don't waste you...
Where is Android Studio layout preview?
...was using the Dracula theme and had to switch back to the Default theme in order to see the "Design" and "Text" tabs visible at the bottom. Cheers.
– Joshua Pinter
Sep 19 '13 at 1:39
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java.lang.NoClassDefFoundError: Could not initialize class XXX
...likely the cause of the problem (maybe file can't be found, no permissions etc.).
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How to use sed/grep to extract text between two words?
...n the grep included in *BSD, or the ones that come with any SVR4 (Solaris, etc). In FreeBSD, you can install the devel/pcre port which includes pcregrep, which supports PCRE (and look-ahead/behind). Older versions of OSX used GNU grep, but in OSX Mavericks, -P is derived from FreeBSD's version, whi...
What are the differences between a UIView and a CALayer?
...CALayer, which inherit from NSObject, mainly focus on rendering, animation etc.
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How to prevent ReflectionTypeLoadException when calling Assembly.GetTypes()
... Whatever the reason for the type load exception, FileNotFound, BadImage, etc, will still throw on every access to the types that are in issue.
– sweetfa
Oct 16 '12 at 1:27
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Why doesn't Java Map extend Collection?
...ement appears in the bag).
This structure would allow intersection, union etc. of a range of "collections". Hence, the hierarchy should be:
Set
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Relation
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When increasing the size of VARCHAR column on a large table could there be any problems?
...har(max) is not. Because varchar(max) values (aka BLOB values - image/text etc) are stored differently on the disk, not within a table row, but "out of row". So the server will go nuts on a big table and become unresponsive for minutes (hours).
--no downtime
ALTER TABLE MyTable ALTER COLUMN [MyColu...
Insert a line break in mailto body
...his also applies to all url schemes such as gopher, smtp, sdp, imap, ldap, etc..
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