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Select first 4 rows of a data.frame in R
How can I select the first 4 rows of a data.frame :
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How to change facet labels?
I have used the following ggplot command:
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How to convert an IPv4 address into a integer in C#?
I'm looking for a function that will convert a standard IPv4 address into an Integer. Bonus points available for a function that will do the opposite.
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Int division: Why is the result of 1/3 == 0?
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+1 and it always rounds down. int i = .99999999 sets int to 0. More specifically, it takes the integer portion and discards the rest.
– Byron Whitlock
Jan 13 '11 at 21:30
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How to input a regex in string.replace?
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How do I delete an exported environment variable?
Before installing gnuplot, I set the environment variable GNUPLOT_DRIVER_DIR = /home/gnuplot/build/src . During the installation, something went wrong.
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What are the true benefits of ExpandoObject?
The ExpandoObject class being added to .NET 4 allows you to arbitrarily set properties onto an object at runtime.
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App Inventor 2 中的响应式设计 · App Inventor 2 中文网
...xels.
For example, to make a button whose width is half the screen width, set the button’s width to be 50 percent rather than setting it to a specific number of pixels.
“Percentage” here means percentage of the screen width or height, not percentage of a containing component. For a button ...
Any shortcut to initialize all array elements to zero?
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A default value of 0 for arrays of integral types is guaranteed by the language spec:
Each class variable, instance variable, or array component is initialized with a default value when it is created (§15.9, §15.10) [...] F...
Undefined method 'task' using Rake 0.9.0
...he latest version ( 0.9.0.beta.4 ) and the rake command ends up with the following error message:
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