remove "empty" elements from multidimensional array

Question

I have a multidimensional array something like this

[ [[]], [[1], [2]], [[1, 2]] ]

What's the best way to remove the empty array?

Right now I am just doing a array[1..-1] to remove the first element but I would like a more reliable way to do it.

@muistooshort note that your array is different from mine. i'll be comparing it against other arrays to find the shortest substring. i'm getting this by doing something like ar.each_index.map{ |i| ar.combination(i).to_a — Brand
– Brand, Commented Oct 26, 2011 at 1:19
So you're saying that you can't get [[],[1]] as an element? I'm just trying to clarify what your data really looks like. — mu is too short
– mu is too short, Commented Oct 26, 2011 at 1:37
@muistooshort yep, can't get [[], [1]]. but you can get [ [[]], [[1], [2]] ] for example. — Brand
– Brand, Commented Oct 26, 2011 at 6:54

Douglas F Shearer · Accepted Answer · 2011-10-25 16:02:22Z

8

Flatten each array and if it has no elements in it, delete it.

arr = [ [[]], [[1], [2]], [[1, 2]] ]
arr = arr.delete_if { |elem| elem.flatten.empty? }
# => [[[1], [2]], [[1, 2]]]

answered Oct 25, 2011 at 16:02

Douglas F Shearer

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