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Remove an entire column from a data.frame in R
Does anyone know how to remove an entire column from a data.frame in R? For example if I am given this data.frame:
6 Answer...
Formula to determine brightness of RGB color
I'm looking for some kind of formula or algorithm to determine the brightness of a color given the RGB values. I know it can't be as simple as adding the RGB values together and having higher sums be brighter, but I'm kind of at a loss as to where to start.
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Select datatype of the field in postgres
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Wayne ConradWayne Conrad
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IIS7 deployment - duplicate 'system.web.extensions/scripting/scriptResourceHandler' section
...ploy a .net 3.5 website on the default app pool in IIS7 having the framework section set to 4.0, I get the following error.
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What is the facade design pattern?
...rmal classes. What is important is how they are structured and how they work together to solve a given problem in the best possible way.
The Facade design pattern simplifies the interface to a complex system; because it is usually composed of all the classes which make up the subsystems of the com...
Checking if an object is a given type in Swift
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If you want to check against a specific type you can do the following:
if let stringArray = obj as? [String] {
// obj is a string array. Do something with stringArray
}
else {
// obj is not a string array
}
You can use "as!" and that...
What is the significance of initializing direction arrays below with given values when developing ch
...nd bottom right is 4,4 and shown what move each index of the arrays will make from the central point, X, at 2,2.)
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.536.
.1X0.
.724.
.....
The way it is set up, if you do ^1 (^ being bitwise XOR) on the index you get the opposite direction - 0 and 1 are opposites, 2 and 3 are opposites and s...
Java: Get first item from a collection
...trs , how can I get the first item out? I could just call an Iterator , take its first next() , then throw the Iterator away. Is there a less wasteful way to do it?
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What is the difference between Class.getResource() and ClassLoader.getResource()?
...ing a stand-alone Java application that continuously loaded a file from disk using the getResourceAsStream ClassLoader method. I was able to edit the file, and the changes were reflected immediately, i.e., the file was reloaded from disk without caching.
However:
I'm working on a project with seve...
Check OS version in Swift?
I'm trying to check system information in Swift. I figured out, that it could be achieved by code:
19 Answers
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