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How to drop rows of Pandas DataFrame whose value in a certain column is NaN
I have this DataFrame and want only the records whose EPS column is not NaN :
12 Answers
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Rails: create on has_one association
...) would work. However there is a big difference between has_many relations and has_one relations:
With a has_many relation, shops returns an ActiveRecord collection object, which has methods that you can use to add and remove shops to/from a user. One of those methods is create, which creates a new...
Validate uniqueness of multiple columns
Is there a rails-way way to validate that an actual record is unique and not just a column? For example, a friendship model / table should not be able to have multiple identical records like:
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Programmatically get the cache line size?
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@android : I use fedora-18 x64 machine with core-i5 processor. cat /sys/devices/system/cpu/cpu0/cache/index0/coherency_line_size returns 64 in my system. Same for index1,2,3 folders also.
– Abid Rahman ...
Meaning of acronym SSO in the context of std::string
In a C++ question about optimization and code style , several answers referred to "SSO" in the context of optimizing copies of std::string . What does SSO mean in that context?
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Removing non-repository files with git?
I'm writing Autotools code and in the process of development, tons of files are generated.
1 Answer
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How to output in CLI during execution of PHP Unit tests?
...lized another way to do this that works much better than the --verbose command line option:
class TestSomething extends PHPUnit_Framework_TestCase {
function testSomething() {
$myDebugVar = array(1, 2, 3);
fwrite(STDERR, print_r($myDebugVar, TRUE));
}
}
This lets you dump ...
MbUnit under Linux, used within an F# project?
...es not read his email very often :-) Seeing as SO has tags for both Gallio and MbUnit, I thought it was worth asking here.
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Remove leading zeros from a number in Javascript [duplicate]
What is the simplest and cross-browser compatible way to remove leading zeros from a number in Javascript ?
3 Answers
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How to use `subprocess` command with pipes
...or various reasons, not least of which is security. Instead, create the ps and grep processes separately, and pipe the output from one into the other, like so:
ps = subprocess.Popen(('ps', '-A'), stdout=subprocess.PIPE)
output = subprocess.check_output(('grep', 'process_name'), stdin=ps.stdout)
ps....