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Pass a data.frame column name to a function
...all foo() like this:
foo(dat,z,x,y)
The problem here is that df$col1 doesn't evaluate the expression col1. It simply looks for a column in df literally called col1. This behavior is described in ?Extract under the section "Recursive (list-like) Objects".
The simplest, and most often recommend...
What is the difference between partitioning and bucketing a table in Hive ?
...ies. Other drawback is having too many partitions is the large number of Hadoop files and directories that are created unnecessarily and overhead to NameNode since it must keep all metadata for the file system in memory.
Bucketing is another technique for decomposing data sets into more manageable p...
C++ Structure Initialization
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What is the difference between doing that, and actually using dot notation to access MORE ACCURATELY the field itself, its not like you are saving any space if that's what the concern is. I really don't get C++ programmers when it comes to being consisten...
How to “warm-up” Entity Framework? When does it get “cold”?
...ion. Especially, for those queries that take very long to compile and that don't change. That way you move the performance overhead from runtime to compile time. Also this won't introduce any lag. But of course this change goes through to the database, so it's not so easy to deal with. Code is more ...
MySQL: #126 - Incorrect key file for table
...IT
It is also worth noting that this can be caused by a full ramdisk when doing things like altering a large table if you have a ramdisk configured. You can temporarily comment out the ramdisk line to allow such operations if you can't increase the size of it.
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Preserve line breaks in angularjs
...on @pilau s answer - but with an improvement that even the accepted answer does not have.
<div class="angular-with-newlines" ng-repeat="item in items">
{{item.description}}
</div>
/* in the css file or in a style block */
.angular-with-newlines {
white-space: pre-wrap;
}
This ...
How to find NSDocumentDirectory in Swift?
I'm trying to get path to Documents folder with code:
9 Answers
9
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Is there a unique Android device ID?
Do Android devices have a unique ID, and if so, what is a simple way to access it using Java?
52 Answers
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Should I use @EJB or @Inject
...fference between @Inject and @EJB but I did not get any wiser. I have not done Java EE before nor do I have experience with dependency injection so I do not understand what I should use?
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How to instantiate non static inner class within a static method?
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For static inner, can't you just simply do Inner inner = new Inner() ?
– Can Lu
May 20 '14 at 8:29
1
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