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Get individual query parameters from Uri [duplicate]
... Note that Uri.Query will only work on absolute Uri. On relative one it throws an InvalidOperationExeception.
– ghord
Jun 23 '13 at 11:46
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Omit rows containing specific column of NA
...y return rows with no NAs
If you want to eliminate all rows with at least one NA in any column, just use the complete.cases function straight up:
DF[complete.cases(DF), ]
# x y z
# 2 2 10 33
Or if completeFun is already ingrained in your workflow ;)
completeFun(DF, names(DF))
...
Callback functions in Java
... but there are many others in the package java.util.function. Most notable ones are
Supplier: void -> A
Consumer: A -> void
BiConsumer: (A,B) -> void
Function: A -> B
BiFunction: (A,B) -> C
and many others that specialize on some of the input/output type. Then, if it doesn't provide...
How to use a filter in a controller?
...zlowski.opensource is better than this because it reduces "magic strings". One benefit - what if this was in a much more complex controller and you failed to unit test the filter being used? You wouldn't notice the error if you use $filter('filtter1') (2 t's). However, if you inject filtter1Filter A...
Do sealed classes really offer performance Benefits?
...ze on the algorithmic level before you optimize on the code-level.
Here's one link mentioning this: Rambling on the sealed keyword
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How can I trim leading and trailing white space?
...terstrip.white=TRUE.
If you want to clean strings afterwards you could use one of these functions:
# Returns string without leading white space
trim.leading <- function (x) sub("^\\s+", "", x)
# Returns string without trailing white space
trim.trailing <- function (x) sub("\\s+$", "", x)
# ...
Just what is an IntPtr exactly?
...epresents a physical location in memory. A null pointer is (almost always) one that points to 0, and is widely recognized as "not pointing to anything". Since systems have different amounts of supported memory, it doesn't always take the same number of bytes to hold that number, so we call a "native...
Implements vs extends: When to use? What's the difference?
...from C++ (referring to classes that inherit characteristics from more than one other class), Java does not allow this, but it does have keyword interface, which is sort of like a pure virtual class in C++. As mentioned by lots of people, you extend a class (and you can only extend from one), and yo...
What is The difference between ListBox and ListView
...ve">
<ListView.Resources>
<GridView x:Key="one">
<GridViewColumn Header="ID" >
<GridViewColumn.CellTemplate>
<DataTemplate>
<TextBlock Text="{Binding id}" /...
Never seen before C++ for loop
...it's very different than the semi-colon, it lets you do multiple things in one section of the for loop (in this case, it initialized two variables). Last time I checked these unusual constructs weren't considered the most readable solution possible and may therefore be frowned-upon by some.
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