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How do I delete rows in a data frame?
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The key idea is you form a set of the rows you want to remove, and keep the complement of that set.
In R, the complement of a set is given by the '-' operator.
So, assuming the data.frame is called myData:
myData[-c(2, 4, 6), ] # notice the -
Of course, don't forget to "reassign" ...
How can I open the interactive matplotlib window in IPython notebook?
I am using IPython with --pylab=inline and would sometimes like to quickly switch to the interactive, zoomable matplotlib GUI for viewing plots (the one that pops up when you plot something in a terminal Python console). How could I do that? Preferably without leaving or restarting my notebook.
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How to format time since xxx e.g. “4 minutes ago” similar to Stack Exchange sites
...answered Jul 5 '10 at 7:45
Sky SandersSky Sanders
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Need a simple explanation of the inject method
...umulator: the result of each run of the block is stored in the accumulator and then passed to the next execution of the block. In the case of the code shown above, you are defaulting the accumulator, result, to 0. Each run of the block adds the given number to the current total and then stores the r...
Difference between VARCHAR and TEXT in MySQL [duplicate]
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VARCHAR(M)
variable max size of M characters
M needs to be between 1 and 65535
takes 1 + c bytes (for M ≤ 255) or 2 + c (for 256 ≤ M ≤ 65535) bytes of disk space where c is the length of the stored string
can be part of an index
More Details
TEXT has a fixed max size of 2¹⁶-1 = 655...
How to enumerate an enum with String type?
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print($0.rawValue)
}
Compatibility with earlier Swift versions (3.x and 4.x)
If you need to support Swift 3.x or 4.0, you may mimic the Swift 4.2 implementation by adding the following code:
#if !swift(>=4.2)
public protocol CaseIterable {
associatedtype AllCases: Collection where AllC...
Is it possible to use jQuery .on and hover?
...after the initial page load. I'm currently using .bind with mouseover and mouseout .
10 Answers
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is it possible to evenly distribute buttons across the width of an android linearlayout
...ally) that contains 3 buttons. I want the 3 buttons to have a fixed width and be evenly distributed across the width of the linear layout.
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Create ArrayList from array
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Yep. And in the (most common) case where you just want a list, the new ArrayList call is unecessary as well.
– Calum
Oct 1 '08 at 14:41
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How to replace plain URLs with links?
I am using the function below to match URLs inside a given text and replace them for HTML links. The regular expression is working great, but currently I am only replacing the first match.
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