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Does pandas iterrows have performance issues?
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Generally, iterrows should only be used in very, very specific cases. This is the general order of precedence for performance of various operations:
1) vectorization
2) using a custom cython routine
3) apply
a) reductions tha...
Reflection: How to Invoke Method with parameters
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Change "methodInfo" to "classInstance", just like in the call with the null parameter array.
result = methodInfo.Invoke(classInstance, parametersArray);
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How to prevent UINavigationBar from covering top of view in iOS 7?
After updating to Xcode 5, the navigation bars in all of my app's views have shifted down. Here are some screenshots, the first showing everything in the view as it's pulled down, and the second showing all of it untouched. The search bar should begin where the navigation bar.
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Counting null and non-null values in a single query
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If I understood correctly you want to count all NULL and all NOT NULL in a column...
If that is correct:
SELECT count(*) FROM us WHERE a IS NULL
UNION ALL
SELECT count(*) FROM us WHERE a IS NOT NULL
Edited to have the full query, after reading the comments :]
S...
How to tell if a string contains a certain character in JavaScript?
...tion does. There are a lot of people who don't understand regex, and generally the simpler answer is the best.
– kemiller2002
Oct 13 '15 at 19:19
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Gradle buildscript dependencies
... level are used to fetch the dependencies that your project depends on. So all the dependencies you need to compile your project.
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Django dump data for a single model?
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As of version 1.1 and greater, the Django dumpdata management command allows you to dump data from individual tables:
./manage.py dumpdata myapp1 myapp2.my_model
You can also separate multiple apps and models on the command line. Here's the canonical definition:
django-admin dumpdata [app_l...
Find the closest ancestor element that has a specific class
... ((el = el.parentElement) && !((el.matches || el.matchesSelector).call(el,sel)));
return el;
}
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Weird “[]” after Java method signature
... Java platform, a declaration form
for a method that returns an array is allowed to place (some or all of) the empty
bracket pairs that form the declaration of the array type after the parameter list.
This is supported by the obsolescent production:
MethodDeclarator:
Meth...
How to install a private NPM module without my own registry?
...on't want to upload to the central registry. The question is, how do I install it from other projects?
14 Answers
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