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Pandas count(distinct) equivalent
I am using pandas as a db substitute as I have multiple databases (oracle, mssql, etc) and I am unable to make a sequence of commands to a SQL equivalent.
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Running a specific test case in Django when your app has a tests directory
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Checkout django-nose. It allows you to specify tests to run like:
python manage.py test another.test:TestCase.test_method
or as noted in comments, use the syntax:
python manage.py test another.test.TestCase.test_method
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check if a std::vector contains a certain object? [duplicate]
Is there something in <algorithm> which allows you to check if a std:: container contains something? Or, a way to make one, for example:
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What is the command to list the available avdnames
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edited May 8 '18 at 9:02
Günter Zöchbauer
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Is there an exponent operator in C#?
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edited Aug 16 at 23:24
Neuron
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Time complexity of Sieve of Eratosthenes algorithm
.../5 + … n/97 is not O(n), because the number of terms is not constant. [Edit after your edit: O(n2) is too loose an upper bound.] A loose upper-bound is n(1+1/2+1/3+1/4+1/5+1/6+…1/n) (sum of reciprocals of all numbers up to n), which is O(n log n): see Harmonic number. A more proper upper-bound i...
C# Sanitize File Name
...cently have been moving a bunch of MP3s from various locations into a repository. I had been constructing the new file names using the ID3 tags (thanks, TagLib-Sharp!), and I noticed that I was getting a System.NotSupportedException :
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Why does ('0' ? 'a' : 'b') behave different than ('0' == true ? 'a' : 'b') [duplicate]
...true:
String: The result is false if the argument is the empty String (its length is zero);
otherwise the result is true.
Now to '0' == true.
Two type conversions will take place here. We can follow this in the specification, section 11.9.3, The Abstract Equality Comparison Algorithm.
Th...
How do I parse a URL query parameters, in Javascript? [duplicate]
...ocation.search;
var query = url.substr(1);
var result = {};
query.split("&").forEach(function(part) {
var item = part.split("=");
result[item[0]] = decodeURIComponent(item[1]);
});
return result;
}
actually it's not that simple, see the peer-review in the comments, especially...
Uniq by object attribute in Ruby
...'s the most elegant way to select out objects in an array that are unique with respect to one or more attributes?
14 Answer...