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Drop unused factor levels in a subsetted data frame
...df,function(x) if(is.factor(x)) factor(x) else x) ...Is drop.levels() much more efficient computationally or better with large data sets? (One would have to rewrite the line above in a for-loop for a huge data frame, I suppose.)
– hatmatrix
Jul 29 '09 at 17:09
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What is Weak Head Normal Form?
...mory stats with :set +s. You can then see that foldl' f ends up allocating more thunks than foldl' f'.
– hammar
Jun 2 '17 at 15:34
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Is Safari on iOS 6 caching $.ajax results?
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What's the meaning of 'origin' in 'git push origin master'
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Replace non-numeric with empty string
...ed Jan 22 '09 at 19:58
Chris Cudmore
27.5k1212 gold badges5252 silver badges9292 bronze badges
answered Nov 4 '08 at 16:54
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How Can I Download a File from EC2 [closed]
... copy the file into the current folder on the local machine.
You can read more here on how to access your instance with ssh if you haven't done already:
http://docs.aws.amazon.com/gettingstarted/latest/computebasics-linux/getting-started-deploy-app-connect-linux.html
When you are able to ssh as...
List of ANSI color escape sequences
... terms, then it contains a term for brown.
If a language contains eight or more terms, then it contains terms for purple, pink, orange or gray.
This may be why story Beowulf only contains the colours black, white, and red. It may also be why the Bible does not contain the colour blue. Homer's Odyss...
What is the overhead of creating a new HttpClient per call in a WebAPI client?
...ared between requests for these handlers also needs to be provided.
The more you use the features of HttpClient, the more you will see that reusing an existing instance makes sense.
However, the biggest issue, in my opinion is that when a HttpClient class is disposed, it disposes HttpClientHandl...
How do I execute a string containing Python code in Python?
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python design patterns [closed]
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You can get started here and here.
For a more in depth look at design pattners you should look at Design Patterns: Elements of Reusable Object-Oriented Software. The source code is not in Python, but it doesn't need to be for you to understand the patterns.
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