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Efficiently checking if arbitrary object is NaN in Python / numpy / pandas?
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pandas.isnull() (also pd.isna(), in newer versions) checks for missing values in both numeric and string/object arrays. From the documentation, it checks for:
NaN in numeric arrays, None/NaN in object arrays
Quick example:
import pandas as pd
import numpy as np
s = pd.Series(['...
Do fragments really need an empty constructor?
I have a Fragment with a constructor that takes multiple arguments. My app worked fine during development, but in production my users sometimes see this crash:
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What difference is there between WebClient and HTTPWebRequest classes in .NET?
...raction built on top of HttpWebRequest to simplify the most common tasks. For instance, if you want to get the content out of an HttpWebResponse, you have to read from the response stream:
var http = (HttpWebRequest)WebRequest.Create("http://example.com");
var response = http.GetResponse();
var st...
git merge: apply changes to code that moved to a different file
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I had a similar issue, and I resolved it by rebasing my work to match the target file organization.
Say that you modified original.txt on your branch (the local branch), but on the master branch, original.txt has been copied to another one, say copy.txt.
This copy has been done in ...
How to import other Python files?
How do I import other files in Python?
19 Answers
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Time complexity of Sieve of Eratosthenes algorithm
...cals of all numbers up to n), which is O(n log n): see Harmonic number. A more proper upper-bound is n(1/2 + 1/3 + 1/5 + 1/7 + …), that is sum of reciprocals of primes up to n, which is O(n log log n). (See here or here.)
The "find the next prime number" bit is only O(n) overall, amortized — yo...
Remove file from the repository but keep it locally
I have a folder which I'd like to remove in my remote repository. I'd like to delete it, but keep the folder in my computer
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How to get String Array from arrays.xml file
...an array that I have in my arrays.xml . When I try to run it in the emulator, I get a force close message.
3 Answers
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Find all files with a filename beginning with a specified string?
I have a directory with roughly 100000 files in it, and I want to perform some function on all files beginning with a specified string, which may match tens of thousands of files.
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How to skip “are you sure Y/N” when deleting files in batch files
I can't for the life of me remember how to bypass the annoying prompt are you sure? Y/N when deleting files.
4 Answers
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