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Group by multiple columns in dplyr, using string vector input
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Does the call to one_of() do anything here? I think it is redundant in this context, as the expression is wrapped in a call to vars().
– knowah
Aug 15 '19 at 14:13
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NULL vs nullptr (Why was it replaced?) [duplicate]
...problem" of my answer, plus it's a nice reference. This answer is just a small part of the reasons.
– Cheers and hth. - Alf
Dec 11 '13 at 3:22
1
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Use of alloc init instead of new
...be using a different method, such as [[SomeObject alloc] initWithString: @"Foo"]. If you're used to writing this, you get in the habit of doing it this way and so [[SomeObject alloc] init] may come more naturally that [SomeObject new].
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Case insensitive string compare in LINQ-to-SQL
... accurate when you're trying to do case insensitive equality checks.
Ideally, the best way to do a case-insensitive equality check would be:
String.Equals(row.Name, "test", StringComparison.OrdinalIgnoreCase)
NOTE, HOWEVER that this does not work in this case! Therefore we are stuck with ToUpp...
JavaScript, elegant way to check nested object properties for null/undefined [duplicate]
...e of using the app this gets populated. Let's say somwhere, after an AJAX call or something i do this:
4 Answers
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Can C++ code be valid in both C++03 and C++11 but do different things?
... // #1
void f(...); // #2
template<int N> void g() {
f(0*N); // Calls #2; used to call #1
}
Rounded results after integer division and modulo
In C++03 the compiler was allowed to either round towards 0 or towards negative infinity. In C++11 it is mandatory to round towards 0
int i = (-1) ...
What does the `forall` keyword in Haskell/GHC do?
I'm beginning to understand how the forall keyword is used in so-called "existential types" like this:
8 Answers
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Setting variable to NULL after free
... int *nPtr=NULL;. Now, I would agree that this would be redundant, with a malloc following right in the next line. However, if there is code between the declaration and the first initialization, somebody might start using the variable even though it has no value yet. If you null-initialize, you get ...
How do you overcome the HTML form nesting limitation?
...o check what button was clicked.
And then I would implement a Javascript call tying into the form's onsubmit event which would check before the form was submitted, and only submit the relevant data to the server (possibly through a second form on the page with the ID needed to process the thing as ...
How do I remove all .pyc files from a project?
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You are not quoting {}. What would happen if accidentally word-split and deleted an intermediate path which happens to be called like a fragment of the path you found?
– Robottinosino
Apr 3 '13 at 2:58
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