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Sample random rows in dataframe
...propriate function that would return a specified number of rows picked up randomly without replacement from a data frame in R language? Can anyone help me out?
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Is there a limit to the length of a GET request? [duplicate]
... place any a priori limit on the length of
a URI. Servers MUST be able to handle the URI of any resource they
serve, and SHOULD be able to handle URIs of unbounded length if they
provide GET-based forms that could generate such URIs. A server
SHOULD return 414 (Request-URI Too Long) status if a URI ...
“The page you are requesting cannot be served because of the extension configuration.” error message
... register version of .NET framework you are using.
This is a common issue and happens when IIS is installed after VS or .NET framework.
Note - for Windows 8/10 users, see the other answer by JohnOpincar below. And also the comment/tip from Kevin Brydon.
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Factors in R: more than an annoyance?
... data types in R is factors. In my experience factors are basically a pain and I never use them. I always convert to characters. I feel oddly like I'm missing something.
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what is the difference between sendStickyBroadcast and sendBroadcast in Android
What is the difference between sendStickyBroadcast and sendBroadcast in Android?
3 Answers
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In .NET, which loop runs faster, 'for' or 'foreach'?
...hrough a list with foreach than it does to loop through an array with for, and you're calling that insignificant? That kind of a performance difference might matter for your application, and it might not, but I wouldn't just dismiss it out of hand.
– Robert Harvey
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Favorite way to create an new IEnumerable sequence from a single value?
...T item)
{
T[] single = { item };
return single;
}
Or even better and shorter, just
public static IEnumerable<T> Yield<T>(this T item)
{
yield return item;
}
Perhaps this is exactly what Enumerable.Repeat is doing under the hood.
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Is it possible to make anonymous inner classes in Java static?
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No, you can't, and no, the compiler can't figure it out. This is why FindBugs always suggests changing anonymous inner classes to named static nested classes if they don't use their implicit this reference.
Edit: Tom Hawtin - tackline says...
Best way for a 'forgot password' implementation? [closed]
...: revised in May 2013 for a better approach
The user enters his username and hits "forgot password". I also recommend the option of entering the email address instead of the username, because usernames are sometimes forgotten too.
The system has a table password_change_requests with the columns ID...
check if variable is dataframe
when my function f is called with a variable I want to check if var is a pandas dataframe:
2 Answers
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