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What encoding/code page is cmd.exe using?
...
Yes, it’s frustrating—sometimes type and other programs
print gibberish, and sometimes they do not.
First of all, Unicode characters will only display if the
current console font contains the characters. So use
a TrueType font like Lucida Console instead of the...
Simultaneously merge multiple data.frames in a list
... issue here is that each data.frame differs in terms of the number of rows and columns, but they all share the key variables (which I've called "var1" and "var2" in the code below). If the data.frames were identical in terms of columns, I could merely rbind , for which plyr's rbind.fill would...
Does the ternary operator exist in R?
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As if is function in R and returns the latest evaluation, if-else is equivalent to ?:.
> a <- 1
> x <- if(a==1) 1 else 2
> x
[1] 1
> x <- if(a==2) 1 else 2
> x
[1] 2
The power of R is vectorization. The vectorization of t...
How to drop columns by name in a data frame
I have a large data set and I would like to read specific columns or drop all the others.
11 Answers
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Fastest way to determine if an integer's square root is an integer
... ~35% faster than your 6bits+Carmack+sqrt code, at least with my CPU (x86) and programming language (C/C++). Your results may vary, especially because I don't know how the Java factor will play out.
My approach is threefold:
First, filter out obvious answers. This includes negative numbers and ...
Matplotlib discrete colorbar
...d) is making 0 showup as grey.
For images i often use the cmap.set_bad() and convert my data to a numpy masked array. That would be much easier to make 0 grey, but i couldnt get this to work with the scatter or the custom cmap.
As an alternative you can make your own cmap from scratch, or read-o...
Scala list concatenation, ::: vs ++
Is there any difference between ::: and ++ for concatenating lists in Scala?
4 Answers
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Reduce, fold or scan (Left/Right)?
... operator's two arguments). This way we can cumulate a result.
reduceLeft and reduceRight cumulate a single result.
foldLeft and foldRight cumulate a single result using a start value.
scanLeft and scanRight cumulate a collection of intermediate cumulative results using a start value.
Accumulate...
What is 'Currying'?
I've seen references to curried functions in several articles and blogs but I can't find a good explanation (or at least one that makes sense!)
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In c# is there a method to find the max of 3 numbers?
...e, but not regularly.
(Note that this is likely to be more efficient than Andrew's LINQ-based answer - but obviously the more elements you have the more appealing the LINQ approach is.)
EDIT: A "best of both worlds" approach might be to have a custom set of methods either way:
public static class...