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Getting the count of unique values in a column in bash
... count the frequency of occurrence of the different values in a column for all the files in a folder and sort them in decreasing order of count (highest count first). How would I accomplish this in a Linux command line environment?
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How can I get query string values in JavaScript?
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For a querystring of ?mykey=0&m.+key=1, calling getParameterByName("m.+key") would return 0 instead of 1. You need to escape the regular expression metacharacters in name before building your regular expression. And you only need to call .replace() once by using t...
How do I create a new Swift project without using Storyboards?
Creating a new project in XCode 6 doesn't allow to disable Storyboards. You can only select Swift or Objective-C and to use or not Core Data.
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Empty arrays seem to equal true and false at the same time
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You're testing different things here.
if (arr) called on object (Array is instance of Object in JS) will check if the object is present, and returns true/false.
When you call if (arr == false) you compare values of this object and the primitive false value. Internally, a...
Android: How to stretch an image to the screen width while maintaining aspect ratio?
... always roughly square) and display it so that it fills the screen horizontally, and stretches vertically to maintain the aspect ratio of the image, on any screen size. Here is my (non-working) code. It stretches the image horizontally, but not vertically, so it is squashed...
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URLWithString: returns nil
...llowing API webStringURL = [stringURL stringByAddingPercentEncodingWithAllowedCharacters:NSCharacterSet.URLQueryAllowedCharacterSet];
– Rushabh
Oct 24 '17 at 0:37
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How can I select rows with most recent timestamp for each key value?
...aster than other answers, at least in my case.
– rain_
Sep 6 '17 at 7:51
@rain_ It really depends on the use case. The...
What is a semaphore?
...s bouncers at a nightclub. There are a dedicated number of people that are allowed in the club at once. If the club is full no one is allowed to enter, but as soon as one person leaves another person might enter.
It's simply a way to limit the number of consumers for a specific resource. For exampl...
What's the state of the art in email validation for Rails?
... answered Aug 24 '10 at 9:56
HallelujahHallelujah
77466 silver badges44 bronze badges
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Is there a way to make R beep/play a sound at the end of a script?
...ion sounds in R which should work cross-platform. Run the following to install beepr and make a sound:
install.packages("beepr")
library(beepr)
beep()
More info at github: https://github.com/rasmusab/beepr
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