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How to remove a key from Hash and get the remaining hash in Ruby/Rails?
... your five-minutes-of-editing are up, you can always copy, delete, modify, and repost a comment.
– iconoclast
May 13 at 23:17
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Git Extensions: Win32 error 487: Couldn't reserve space for cygwin's heap, Win32 error 0
...anyone, I moved the GitExtensions bit in my PATH to be the very first item and it seems to have resolved the issue for me. (I put the git/cmd itself 2nd - not sure if that was part of it). A bit easier than a reboot or .dll shuffling.
– jinglesthula
Dec 2 '16 ...
Reorder levels of a factor without changing order of values
I have data frame with some numerical variables and some categorical factor variables. The order of levels for those factors is not the way I want them to be.
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valueOf() vs. toString() in Javascript
In Javascript every object has a valueOf() and toString() method. I would have thought that the toString() method got invoked whenever a string conversion is called for, but apparently it is trumped by valueOf().
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MySQL: @variable vs. variable. What's the difference?
...are loosely typed variables that may be initialized somewhere in a session and keep their value until the session ends.
They are prepended with an @ sign, like this: @var
You can initialize this variable with a SET statement or inside a query:
SET @var = 1
SELECT @var2 := 2
When you develop a stor...
ITunes review URL and iOS 7 (ask user to rate our app) AppStore show a blank page
Does anybody knows if the technique used to ask the user to rate our app and open for him the App Store directly on the rating page is still working on iOS 7 ?
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Android Studio installation on Windows 7 fails, no JDK found
I downloaded Android Studio and attempted to launch the program.
29 Answers
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How to check if a table exists in a given schema
Postgres 8.4 and greater databases contain common tables in public schema and company specific tables in company schema.
company schema names always start with 'company' and end with the company number.
So there may be schemas like:
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Why would you use an ivar?
...is question asked the other way, such as Must every ivar be a property? (and I like bbum's answer to this Q).
7 Answers
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Convert RGB to RGBA over white
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Take the lowest color component, and convert that to an alpha value. Then scale the color components by subtracting the lowest, and dividing by the alpha value.
Example:
152 converts to an alpha value of (255 - 152) / 255 ~ 0.404
152 scales using (152 - 1...