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How do I replace NA values with zeros in an R dataframe?

...then assign it to the location/name on the left. In this case, we aren't really "doing" anything - just making zeroes. The left side is saying: look at the d object, inside the d object (the square brackets), find all the elements that return TRUE (is.na(d) returns a logical for each element). Once...
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Function for Factorial in Python

...factorial (available in Python 2.6 and above): import math math.factorial(1000) If you want/have to write it yourself, you can use an iterative approach: def factorial(n): fact = 1 for num in range(2, n + 1): fact *= num return fact or a recursive approach: def factorial(n...
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What is an abstract class in PHP?

...re interface. Also interfaces are a special case of abstract classes where ALL methods are abstract. See this section of the PHP manual for further reference. share | improve this answer |...
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Is git not case sensitive?

In the first commitment of my partial called _Electronics it was written beginning with a capital letters, then I changed it to _electronics . ...
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upstream sent too big header while reading response header from upstream

... to increase the proxy_buffer_size and the proxy_buffers, or disable it totally (Please read the nginx documentation). Example of proxy buffering configuration http { proxy_buffer_size 128k; proxy_buffers 4 256k; proxy_busy_buffers_size 256k; } Example of disabling your proxy buffer ...
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get dictionary value by key

... 10 Answers 10 Active ...
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Time complexity of Sieve of Eratosthenes algorithm

...oose 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 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...
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py2exe - generate single executable file

... PyInstaller will create a single .exe file with no dependencies; use the --onefile option. It does this by packing all the needed shared libs into the executable, and unpacking them before it runs, just as you describe (EDIT: py2ex...
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Why does Javascript's regex.exec() not always return the same value? [duplicate]

... matches by performing the assignment as the loop condition. var re = /foo_(\d+)/g, str = "text foo_123 more text foo_456 foo_789 end text", match, results = []; while (match = re.exec(str)) results.push(+match[1]); DEMO: http://jsfiddle.net/pPW8Y/ If you don't like the placem...
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How to handle invalid SSL certificates with Apache HttpClient? [duplicate]

...thority, but a self signed or issued by a private CMS. Don't panic. All you need to do is to add the server certificate to your trusted Java key store if your client is written in Java. You might be wondering how as if you can not access the machine where the server is installed. ...