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Drop unused factor levels in a subsetted data frame
...
It is a known issue, and one possible remedy is provided by drop.levels() in the gdata package where your example becomes
> drop.levels(subdf)
letters numbers
1 a 1
2 b 2
3 c 3
> levels(dro...
Git: what is a dangling commit/blob and where do they come from?
...st the ability to recover dangling blobs and commits that you may not want now but you might want in the future. Once you run garbage collection you take away some pretty powerful revert functionality from git. Use with caution and as the exception, not the rule. --- Just let git do its thing.
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Correct way to convert size in bytes to KB, MB, GB in JavaScript
...e fixed version below. Aliceljm does not active her copied code anymore
Now, Fixed version unminified, and ES6'ed: (by community)
function formatBytes(bytes, decimals = 2) {
if (bytes === 0) return '0 Bytes';
const k = 1024;
const dm = decimals < 0 ? 0 : decimals;
const sizes...
What is the best way to unit test Objective-C code?
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Xcode 5 now has XCTest does it still include OCUnit? Will you update your answer with information for XCode 5.
– BrightIntelDusk
Mar 24 '14 at 22:48
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Growing Amazon EBS Volume sizes [closed]
I'm quite impressed with Amazon's EC2 and EBS services. I wanted to know if it is possible to grow an EBS Volume.
11 Answer...
What happens to my apps after my developer account membership expires? [closed]
...s just experienced the same thing. They forgot to renew their account, and now the app is no longer available on the app store! Hope the app is still available on the provisioning portal.
– ultravelocity
Jun 7 '11 at 1:57
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What's the difference between `raw_input()` and `input()` in Python 3?
...e raw_input() does not.
Python 3:
raw_input() was renamed to input() so now input() returns the exact string.
Old input() was removed.
If you want to use the old input(), meaning you need to evaluate a user input as a python statement, you have to do it manually by using eval(input()).
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Check if an array is empty or exists
...ypeof array.length; // => "number"
Case Empty Array
Now since we tested all other possibilities, we're talking to an instance of Array. In order to make sure it's not empty, we ask about number of elements it's holding, and making sure it has more than zero elements.
firstArr...
How do you organise multiple git repositories, so that all of them are backed up together?
...ration from project tasks, while most SVN workflows conflate the two; it's now common to see people delegate the administrative part to GitHub or other such providers.)
– Damien Diederen
Mar 22 '10 at 10:45
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Can a C++ enum class have methods?
...IsYellow() const { return value == Banana; }
private:
Value value;
};
Now you can write:
Fruit f = Fruit::Strawberry;
f.IsYellow();
And the compiler will prevent things like:
Fruit f = 1; // Compile time error.
You could easily add methods such that:
Fruit f("Apple");
and
f.ToString(...