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Extracting specific columns from a data frame
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This doesn't use dplyr. It uses base::subset, and is identical to Stephane Laurent's answer except that you use column numbers instead of column names.
– Gregor Thomas
Oct 12 '17 at 18:16
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What is a covariant return type?
...can change the return type as long as it can be assigned to return type of Base version of the method.
So this feature of returning derived types is called COVARIANT...
Can overridden methods differ in return type?
share
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How to get current page URL in MVC 3
...ension method to your code:
public static Uri UrlOriginal(this HttpRequestBase request)
{
string hostHeader = request.Headers["host"];
return new Uri(string.Format("{0}://{1}{2}",
request.Url.Scheme,
hostHeader,
request.RawUrl));
}
And then you can execute it off the Request...
How can we print line numbers to the log in java
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The index will change based on the JVM version. I believe it changed from 1.4 to 1.5.
– Ed Thomas
Sep 23 '08 at 7:17
2
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Coroutine vs Continuation vs Generator
...be thought of as a kind of inside-out continuation. I'll give you a Python based pseudocode example of a continuation.
Say Python had a function called callcc(), and this function took two arguments, the first being a function, and the second being a list of arguments to call it with. The only rest...
How do I print debug messages in the Google Chrome JavaScript Console?
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These functions will log different types of items (which can be filtered based on log, info, error or warn) and will not cause errors when console is not available. These functions will work in Firebug and Chrome consoles.
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what is the difference between sendStickyBroadcast and sendBroadcast in Android
...st()
:- synchronous broadcast
:- receiver receives broadcast in priority base
:- we can also simply abort broadcast in this type
Local Broadcast
:- use only when broadcast is used only inside same process
Sticky Broadcast
:- normal broadcast intent is not available any more after this was sen...
Redirect to named url pattern directly from urls.py in django?
...ganized guy, favoring the DRY principle, so I would like to get the target based on it's named url pattern, rather than hard coding the url.
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gitignore does not ignore folder
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This is not a viable solution based on the original question. @lagos-arpad specifically asked about a subdirectory and not the entire project. Your solution removes everything from the root level of the git repository and this is not a recommended approac...
Converting HTML files to PDF [closed]
...ing (X)HTML-document. The input files (reports) use a rather simple, table-based layout, so support for really fancy JavaScript/CSS stuff is probably not needed.
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