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C++ preprocessor __VA_ARGS__ number of arguments
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Is there an R function for finding the index of an element in a vector?
... that is equal to x . I know that one way to do this is: which(x == v)[[1]] , but that seems excessively inefficient. Is there a more direct way to do it?
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Boolean operators && and ||
...an return a vector, like this:
((-2:2) >= 0) & ((-2:2) <= 0)
# [1] FALSE FALSE TRUE FALSE FALSE
The longer form evaluates left to right examining only the first element of each vector, so the above gives
((-2:2) >= 0) && ((-2:2) <= 0)
# [1] FALSE
As the help page says...
Need a simple explanation of the inject method
I'm looking at this code but my brain is not registering how the number 10 can become the result. Would someone mind explaining what's happening here?
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Unique (non-repeating) random numbers in O(1)?
I'd like to generate unique random numbers between 0 and 1000 that never repeat (i.e. 6 doesn't show up twice), but that doesn't resort to something like an O(N) search of previous values to do it. Is this possible?
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Print second last column/field in awk
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awk '{print $(NF-1)}'
Should work
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Python assigning multiple variables to same value? list behavior
... and Chris Wallace have a hot dog. If you change the first element of a to 1, the first elements of b and c are 1.
If you want to know if two names are naming the same object, use the is operator:
>>> a=b=c=[0,3,5]
>>> a is b
True
You then ask:
what is different from this...
How to scale down a range of numbers with a known min and max value
...anel. I want the height and width of each ellipse to be in a range of say 1-30. I have methods that find the minimum and maximum values from my data set, but I won't have the min and max until runtime. Is there an easy way to do this?
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