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data.table vs dplyr: can one do something well the other can't or does poorly?
...able , not so much with dplyr . I've read through some dplyr vignettes and examples that have popped up on SO, and so far my conclusions are that:
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How do I upgrade my ruby 1.9.2-p0 to the latest patch level using rvm?
...2.
Finally, to install the new ruby version, just run rvm install 1.9.2 - and wait for it to compile!
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How to detect Safari, Chrome, IE, Firefox and Opera browser?
I have 5 addons/extensions for FF, Chrome, IE, Opera, and Safari.
24 Answers
24
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LINQ Aggregate algorithm explained
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The easiest-to-understand definition of Aggregate is that it performs an operation on each element of the list taking into account the operations that have gone before. That is to say it performs the action on the first and second element and carr...
How do I get the number of days between two dates in JavaScript?
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Here is a quick and dirty implementation of datediff, as a proof of concept to solve the problem as presented in the question. It relies on the fact that you can get the elapsed milliseconds between two dates by subtracting them, which coerc...
OAuth 2.0: Benefits and use cases — why?
Could anyone explain what's good about OAuth2 and why we should implement it? I ask because I'm a bit confused about it — here's my current thoughts:
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Finding three elements in an array whose sum is closest to a given number
Given an array of integers, A 1 , A 2 , ..., A n , including negatives and positives, and another integer S. Now we need to find three different integers in the array, whose sum is closest to the given integer S. If there exists more than one solution, any of them is ok.
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Python 3: UnboundLocalError: local variable referenced before assignment [duplicate]
...ather than relying on Globals
def function(Var1, Var2):
if Var2 == 0 and Var1 > 0:
print("Result One")
elif Var2 == 1 and Var1 > 0:
print("Result Two")
elif Var1 < 1:
print("Result Three")
return Var1 - 1
function(1, 1)
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Entity Attribute Value Database vs. strict Relational Model Ecommerce
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There's a few general pros and cons I can think of, there are situations where one is better than the other:
Option 1, EAV Model:
Pro: less time to design and develop a simple application
Pro: new entities easy to add (might even
be added by users?)...
Finding duplicate values in MySQL
I have a table with a varchar column, and I would like to find all the records that have duplicate values in this column. What is the best query I can use to find the duplicates?
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