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Selecting data frame rows based on partial string match in a column
...ke% "Merc", ]
iris[iris$Species %like% "osa", ]
If that is what you had, then perhaps you had just mixed up row and column positions for subsetting data.
If you don't want to load a package, you can try using grep() to search for the string you're matching. Here's an example with the mtcars dat...
async await return Task
... means into a synchronous method? If I try to change the method to async then VS complain about it.
5 Answers
...
Create request with POST, which response codes 200 or 201 and content
...
Location: http://stackoverflow.com/a/36373586/12597
Response body
They then go on to mention what you should include in the response body:
The 201 response payload typically describes and links to the resource(s) created.
For the human using the browser, you give them something they can lo...
Does deleting a branch in git remove it from the history?
...runk'.
If the branch was merged into another branch before it was deleted then all of the commits will still be reachable from the other branch when the first branch is deleted. They remain exactly as they were.
If the branch is deleted without being merged into another branch then the commits in ...
What techniques can be used to define a class in JavaScript, and what are their trade-offs?
... it is looked up on its prototype(s) (i.e. the object it was cloned from), then the prototype's prototypes and so on.
In other words: there are no classes.
JavaScript actually has a nice tweak of that model: constructors. Not only can you create objects by copying existing ones, you can also const...
What can MATLAB do that R cannot do? [closed]
I often hear people complain how expensive MATLAB licenses are. Then I wonder why they don't just use Octave or R . But is the latter right? Can you use R to replace MATLAB?
...
What are the risks of running 'sudo pip'?
... to modify system's software with third party tools (pip in this instance) then you have no guarantee about the state of your system. Yet another reason is that sudo can bring you problems you wouldn't have a chance or have a very small chance to have otherwise. See for example Mismatch between sys....
Understanding repr( ) function in Python
...n you call for example repr(x) the interpreter puts 'foo' instead of x and then calls repr('foo').
>>> repr(x)
"'foo'"
>>> x.__repr__()
"'foo'"
repr actually calls a magic method __repr__ of x, which gives the string containing the representation of the value 'foo' assigned to x...
How to access route, post, get etc. parameters in Zend Framework 2
...ted json string, for example, is to read the contents of 'php://input' and then decode it. For example i had a simple Zend route:
'save-json' => array(
'type' => 'Zend\Mvc\Router\Http\Segment',
'options' => array(
'route' => '/save-json/',
...
Is there a way to chain multiple value converters in XAML?
... throw new NotImplementedException();
}
#endregion
}
Which can then be used in XAML like this:
<c:ValueConverterGroup x:Key="InvertAndVisibilitate">
<c:BooleanInverterConverter/>
<c:BooleanToVisibilityConverter/>
</c:ValueConverterGroup>
...