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Differences in boolean operators: & vs && and | vs ||
I know the rules for && and || but what are & and | ? Please explain these to me with an example.
11 Ans...
What is the purpose of setting a key in data.table?
I am using data.table and there are many functions which require me to set a key (e.g. X[Y] ). As such, I wish to understand what a key does in order to properly set keys in my data tables.
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When to use MongoDB or other document oriented database systems? [closed]
We offer a platform for video- and audio-clips, photos and vector-grafics. We started with MySQL as the database backend and recently included MongoDB for storing all meta-information of the files, because MongoDB better fits the requirements. For example: photos may have Exif information, video...
What goes into your .gitignore if you're using CocoaPods?
I've been doing iOS development for a couple of months now and just learned of the promising CocoaPods library for dependency management.
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Correct format specifier for double in printf
What is the correct format specifier for double in printf? Is it %f or is it %lf ? I believe it's %f , but I am not sure.
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How does type Dynamic work and how to use it?
I heard that with Dynamic it is somehow possible to do dynamic typing in Scala. But I can't imagine how that might look like or how it works.
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Is it alright to use target=“_blank” in HTML5?
I recall reading somewhere that in HTML5 it was no longer okay to use target="_blank" in HTML5, but I can't find it now.
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How to determine if binary tree is balanced?
It's been a while from those school years. Got a job as IT specialist at a hospital. Trying to move to do some actual programming now. I'm working on binary trees now, and I was wondering what would be the best way to determine if the tree is height-balanced.
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Python division
I was trying to normalize a set of numbers from -100 to 0 to a range of 10-100 and was having problems only to notice that even with no variables at all, this does not evaluate the way I would expect it to:
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Why is good UI design so hard for some Developers? [closed]
Some of us just have a hard time with the softer aspects of UI design ( myself especially ). Are "back-end coders" doomed to only design business logic and data layers? Is there something we can do to retrain our brain to be more effective at designing pleasing and useful presentation layers?
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