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How to prevent ifelse() from turning Date objects into numeric objects
... to manipulate a date vector. I expected the result to be of class Date , and was surprised to get a numeric vector instead. Here is an example:
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What does “export” do in shell programming? [duplicate]
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Exported variables such as $HOME and $PATH are available to (inherited by) other programs run by the shell that exports them (and the programs run by those other programs, and so on) as environment variables. Regular (non-exported) variables are not availab...
HTML 5 tag vs Flash video. What are the pros and cons?
...'re pondering on how to embed video in your page, just use <video> and don't give it a second thought. This question is only preserved for historical value.
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How to append one file to another in Linux from the shell?
I have two files: file1 and file2 . How do I append the contents of file2 to file1 so that contents of file1 persist the process?
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Hiding the scroll bar on an HTML page
...w: hidden;
}
</style>
The code above hides both the horizontal and vertical scrollbar.
If you want to hide only the vertical scrollbar, use overflow-y:
<style type="text/css">
body {
overflow-y: hidden;
}
</style>
And if you want to hide only the horizonta...
How do you tell someone they're writing bad code? [closed]
...th a small group of people on a coding project for fun. It's an organized and fairly cohesive group. The people I work with all have various skill sets related to programming, but some of them use older or outright wrong methods, such as excessive global variables, poor naming conventions, and oth...
Can I catch multiple Java exceptions in the same catch clause?
...that base exception type.
Also note that you cannot catch both ExceptionA and ExceptionB in the same block if ExceptionB is inherited, either directly or indirectly, from ExceptionA. The compiler will complain:
Alternatives in a multi-catch statement cannot be related by subclassing
Alternative ...
What are good examples of genetic algorithms/genetic programming solutions? [closed]
Genetic algorithms (GA) and genetic programming (GP) are interesting areas of research.
34 Answers
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S3 Error: The difference between the request time and the current time is too large
I have error The difference between the request time and the current time is too large when call method amazons3.ListObjects
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Difference between a Structure and a Union
Is there any good example to give the difference between a struct and a union ?
Basically I know that struct uses all the memory of its member and union uses the largest members memory space. Is there any other OS level difference?
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