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In python lists can be sliced like this x[4:-1] to get from the fourth to the last element.

In R something similar can be accomplished for vectors with x[4:length(x)] and for multidimensional arrays with something like x[,,,,4:dim(x)[5],,,]. Is this more elegant syntax for array slicing for a particular dimension from an element in the middle to the last element?

Thanks

momeara
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    Actually in python, x[4:-1] will skip the last element. To include the last element you just need x[4:], which is equivalent to algoriffic's (1:10)[-(1:4)] in R. – signalseeker Jan 27 '10 at 13:56
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    Also one off at the front! In python x[4:-1] will get the fifth (not the fourth) to the penultimate element. – Epimetheus Aug 13 '15 at 15:29

2 Answers2

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You could use the drop elements syntax:

> (1:10)[-(1:4)]
[1]  5  6  7  8  9 10
AnthonyF
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In case you are interested in slicing the last n elements of the array then you could use:

x[seq(length=n, from=length(x), by=-1)]
Xavier Guardiola
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