How to select the last n % elements of an array in Ruby? -


i have sorted array , keep last 50-60-70% (generally n%) of elements. how can achieve this?

for example 

[1,2,3,4,5,6,7,8,9].last(this.size*0.7)

doesn't work.

you need use tap in order reference object want.

[1,2,3,4,5,6,7,8,9].tap { |this| break this.last(this.size*0.7) }

the break needed because tap ignores block's return value.


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