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What uses are there for “placement new”?
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Placement new allows you to construct an object in memory that's already allocated.
You may want to do this for optimization when you need to construct multiple instances of an object, and it is faster not to re-allocate memory each time y...
Specifying colClasses in the read.csv
... the read.csv function in R. In my data, the first column "time" is basically a character vector while the rest of the columns are numeric.
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javac is not recognized as an internal or external command, operable program or batch file [closed]
...nal or external command... error message.
In a nutshell, you have not installed Java correctly. Finalizing the installation of Java on Windows requires some manual steps. You must always perform these steps after installing Java, including after upgrading the JDK.
Environment variables and PATH
(...
Java: Multiple class declarations in one file
...here's an official term for this approach though.
As for whether this actually changes between implementations - I highly doubt it, but if you avoid doing it in the first place, you'll never need to care :)
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Why are you not able to declare a class as static in Java?
...This method doesn't work
public static InnerClass getAnInnerClassStatically(){
return new InnerClass();
}
}
class OtherClass{
//Use of a static nested class:
private OuterClass.StaticNestedClass staticNestedClass = new OuterClass.StaticNestedClass();
//Doesn't work
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add column to mysql table if it does not exist
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OK this is really crude but someone's got to say it. if you are simply running a SQL script from the command line, you can give mysql the --force switch, which means keep going even if there's an error. then, just go for it. you just want...
Best way to store password in database [closed]
...d thing you are thinking about this and it is a good question, this is actually a duplicate of these questions (at least):
How to best store user information and user login and password
Best practices for storing database passwords
Salting Your Password: Best Practices?
Is it ever ok to store pass...
Proper practice for subclassing UIView?
...Rect , and layoutSubviews . (I'm thinking in terms of setup and teardown callbacks.) In my case, I'm setting up my frame and internal views in layoutSubviews , but I'm not seeing anything onscreen.
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How to export plots from matplotlib with transparent background?
...Matplotlib so as to save you graph as a png file.
And if you want to turn all white pixel transparent, there's this other question : Using PIL to make all white pixels transparent?
If you want to turn an entire area to transparent, then there's this question: And then use the PIL library like in t...
Installing Java on OS X 10.9 (Mavericks)
I have installed the JDK on Mac OS X v10.8 (Mountain Lion). When I upgraded it to Mac OS X v10.9 (Mavericks) and ran java -version in the terminal, it showed:
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