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How do Trigonometric functions work?
...ey do a lousy job of distributing the function approximation's accuracy in order to be "perfect" right near the evaluation point; the error generally zooms upwards as you get away from it. And if you have a function with any noncontinuous derivative (e.g. square waves, triangle waves, and their inte...
How can I check if a string is null or empty in PowerShell?
Is there a built-in IsNullOrEmpty -like function in order to check if a string is null or empty, in PowerShell?
11 Answers...
Git - How to use .netrc file on Windows to save user and password
... GPG before parsing.
Multiple -f arguments are OK. They are processed in order, and the first matching entry found is returned via the credential helper protocol.
When no -f option is given, .authinfo.gpg, .netrc.gpg, .authinfo, and .netrc files in your home directory are used in this order.
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How to solve error “Missing `secret_key_base` for 'production' environment” (Rails 4.1)
...environment variable for the secret_key_base in your production server. In order to solve this error you should follow these steps to create an environment variable for Linux (in my case Ubuntu) in your production server:
In the terminal of your production server execute:
$ RAILS_ENV=production r...
Generate all permutations of a list without adjacent equal elements
...ptotic running time is optimal, since the overhead of generation is on the order of the length of the output. The worst-case delay unfortunately is quadratic; it could be reduced to linear (optimal) with better data structures.
from collections import Counter
from itertools import permutations
from...
How to add elements of a Java8 stream into an existing List
...TE: nosid's answer shows how to add to an existing collection using forEachOrdered(). This is a useful and effective technique for mutating existing collections. My answer addresses why you shouldn't use a Collector to mutate an existing collection.
The short answer is no, at least, not in general,...
Removing duplicates from a list of lists
...[[1, 2], [4], [5, 6, 2], [3]]
Simple to comprehend, and you preserve the order of the first occurrence of each element should that be useful, but I guess it's quadratic in complexity as you're searching the whole of new_k for each element.
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How does lucene index documents?
... Yes, you are correct. The only thing to mention is the final order is defined using sorting rules (relevance index in trivial case), thus the order in which segments are searched isn't relevant.
– Denis Bazhenov
Jul 19 '16 at 5:25
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Getting “type or namespace name could not be found” but everything seems ok?
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The compiler compiles according to the project build order, so if there is a genuine error in one project it can get lost in a sea of red-herring "type or namespace could not be found" errors - because it just exits when it finds the error, and doesn't get to updating the refer...
Why should I not include cpp files and instead use a header?
..., x = y + 1, that means you have to compile all two million lines again in order to test this. And if you find out that you meant to do a x = y - 1 instead, then again, two million lines of compile are waiting for you. That's many hours of time wasted that could be better spent doing anything else...