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How to prevent ifelse() from turning Date objects into numeric objects
...1:5], format: "2010-12-31" "2011-01-02" "2011-01-03" "2011-01-04" "2011-01-05"
dplyr::if_else
From dplyr 0.5.0 release notes:
[if_else] have stricter semantics that ifelse(): the true and false arguments must be the same type. This gives a less surprising return type, and preserves S3 vectors lik...
When to use Windows Workflow Foundation? [closed]
...d project from a consultant which used WF as its backbone. It was prone to errors, corrupted workflows that can't be restarted, an archaic versioning system that requires a complete duplicate of the workflow for any minor changes, horrific generated code, and such a delicate code that you have to ha...
Where is the C auto keyword used?
...(auto versus extrn). If you do not use one or the other, you have a syntax error. That is to say, x, y; is not a declaration by itself, but auto x, y; is.
Since code bases written in B had to be ported to NB and to C as the language was developed, the newer versions of the language carried some bag...
Getter and Setter?
...Foo {
public int bar;
}
Foo myFoo = new Foo();
myFoo.bar = "string"; // error
Using magic methods (__get and __set) also works, but only when accessing a property that has lower visibility than the current scope can access. It can easily give you headaches when trying to debug, if it is not use...
MongoDB relationships: embed or reference?
... If many records will refer to the same data it is more efficient and less error prone to update a single record and keep references to it in other places.
Document size considerations
MongoDB imposes a 4MB (16MB with 1.8) size limit on a single document. In a world of GB of data this sounds small...
Import CSV file to strongly typed data structure in .Net [closed]
...I personally use. It's a bit rough around the edges and has pretty much no error reporting.
public static IList<IList<string>> Parse(string content)
{
IList<IList<string>> records = new List<IList<string>>();
StringReader stringReader = new StringReader(...
Eclipse java debugging: source not found
While debugging a java app in eclipse I receive a " Source not found " error in two cases:
31 Answers
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How to test Spring Data repositories?
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I apologize. I will whip me because of this error. Please try once again!
– JRichardsz
Feb 13 '19 at 14:39
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Show and hide a View with a slide up/down animation
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:thumbs_up: this got rid of a method ambiguity error I was getting
– lasec0203
Apr 11 at 3:36
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show 1 more comm...
Prevent ViewPager from destroying off-screen views
...thod throws : "java.lang.IllegalStateException: Fragment already added:" error for my app.
– alicanbatur
Feb 18 '14 at 14:11
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