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Conditionally Remove Dataframe Rows with R [duplicate]
... tried so many complicated answers -- none worked. Your solution is simple and brilliant.
– WGray
Aug 6 '15 at 20:49
5
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What is the inverse function of zip in python? [duplicate]
I've used the zip() function from the numpy library to sort tuples and now I have a list containing all the tuples. I had since modified that list and now I would like to restore the tuples so I can use my data. How can I do this?
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How to emulate C array initialization “int arr[] = { e1, e2, e3, … }” behaviour with std::array?
(Note: This question is about not having to specify the number of elements and still allow nested types to be directly initialized.)
This question discusses the uses left for a C array like int arr[20]; . On his answer , @James Kanze shows one of the last strongholds of C arrays, it's unique i...
module.exports vs exports in Node.js
... like a function.
2nd least important reason
They set both module.exports and exports to ensure exports isn't referencing the prior exported object. By setting both you use exports as a shorthand and avoid potential bugs later on down the road.
Using exports.prop = true instead of module.exports....
Count number of objects in list [closed]
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length(x)
Get or set the length of vectors (including lists) and factors, and of any other R object for which a method has been defined.
lengths(x)
Get the length of each element of a list or atomic vector (is.atomic) as an integer or numeric vector.
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What is the difference between char array and char pointer in C?
I am trying to understand pointers in C but I am currently confused with the following:
8 Answers
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Find running median from a stream of integers
...n left side to represent elements that are less than the effective median, and a min heap on right side to represent elements that are greater than the effective median.
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generate days from date range
...es, or temp tables. The subquery generates dates for the last 10,000 days, and could be extended to go as far back or forward as you wish.
select a.Date
from (
select curdate() - INTERVAL (a.a + (10 * b.a) + (100 * c.a) + (1000 * d.a) ) DAY as Date
from (select 0 as a union all select 1 un...
Should you declare methods using overloads or optional parameters in C# 4.0?
I was watching Anders' talk about C# 4.0 and sneak preview of C# 5.0 , and it got me thinking about when optional parameters are available in C# what is going to be the recommended way to declare methods that do not need all parameters specified?
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How to make an HTTP POST web request
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There are several ways to perform HTTP GET and POST requests:
Method A: HttpClient (Preferred)
Available in: .NET Framework 4.5+, .NET Standard 1.1+, .NET Core 1.0+ .
It is currently the preferred approach, and is asynchronous and high performance. Use the built-...