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Reorder levels of a factor without changing order of values
I have data frame with some numerical variables and some categorical factor variables. The order of levels for those factors is not the way I want them to be.
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Merging: Hg/Git vs. SVN
I often read that Hg (and Git and...) are better at merging than SVN but I have never seen practical examples of where Hg/Git can merge something where SVN fails (or where SVN needs manual intervention). Could you post a few step-by-step lists of branch/modify/commit/...-operations that show where S...
valueOf() vs. toString() in Javascript
In Javascript every object has a valueOf() and toString() method. I would have thought that the toString() method got invoked whenever a string conversion is called for, but apparently it is trumped by valueOf().
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Convert RGB to RGBA over white
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Take the lowest color component, and convert that to an alpha value. Then scale the color components by subtracting the lowest, and dividing by the alpha value.
Example:
152 converts to an alpha value of (255 - 152) / 255 ~ 0.404
152 scales using (152 - 1...
Does anyone still use [goto] in C# and if so why? [closed]
I was wondering whether anyone still uses the "goto" keyword syntax in C# and what possible reasons there are for doing so.
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Making WPF applications look Metro-styled, even in Windows 7? (Window Chrome / Theming / Theme)
I like the window chrome on the new Office Suite and Visual Studio:
6 Answers
6
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Why would you use an ivar?
...is question asked the other way, such as Must every ivar be a property? (and I like bbum's answer to this Q).
7 Answers
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Which is faster : if (bool) or if(int)?
The above topic made me do some experiments with bool and int in if condition. So just out of curiosity I wrote this program:
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Replace all 0 values to NA
...ays in ?'NULL',
NULL represents the null object in R
which is unique and, I guess, can be seen as the most uninformative and empty object.1 Then it becomes not so surprising that
data.frame(x = c(1, NULL, 2))
# x
# 1 1
# 2 2
That is, R does not reserve any space for this null object.2 Mea...
UnboundLocalError on local variable when reassigned after first use
The following code works as expected in both Python 2.5 and 3.0:
12 Answers
12
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