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Remove trailing zeros
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edited May 23 '17 at 11:47
Community♦
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answered Dec 24 '10 at 11:14
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What are the differences between vector and list data types in R?
...tors are "atomic vectors" in strict R parlance:
aaa <- vector("list", 3)
is.list(aaa) #TRUE
is.vector(aaa) #TRUE
Lists are a "recursive" type (of vector) whereas atomic vectors are not:
is.recursive(aaa) # TRUE
is.atomic(aaa) # FALSE
You process data objects with different functions...
Normal arguments vs. keyword arguments
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352
There are two related concepts, both called "keyword arguments".
On the calling side, which i...
Why did Rails4 drop support for “assets” group in the Gemfile
In Rails 3, gems used exclusively to generate assets in the asset pipeline were properly placed in the assets group of the Gemfile:
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How can I create a UIColor from a hex string?
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132
This is great except it doesn't do what the questioner asks, which is to convert a hex STRING into a UIColor. This converts an integer to a...
Docker: adding a file from a parent directory
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231
You can build the Dockerfile from the parent directory:
docker build -t <some tag> -f &l...
Select multiple records based on list of Id's with linq
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answered May 29 '13 at 21:53
YuckYuck
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Efficient way to remove keys with empty strings from a dict
...n 2.X
dict((k, v) for k, v in metadata.iteritems() if v)
Python 2.7 - 3.X
{k: v for k, v in metadata.items() if v is not None}
Note that all of your keys have values. It's just that some of those values are the empty string. There's no such thing as a key in a dict without a value; if it d...
Grep characters before and after match?
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3 characters before and 4 characters after
$> echo "some123_string_and_another" | grep -o -P '.{0,3}string.{0,4}'
23_string_and
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How to get an array of specific “key” in multidimensional array without looping
... must support php > 5.5, the following alternatives exist:
Since php 5.3, you can use array_map with an anonymous function, like this:
$ids = array_map(function ($ar) {return $ar['id'];}, $users);
Before(Technically php 4.0.6+), you must create an anonymous function with create_function inste...