How to select elements from array in Julia matching predicate?

You can use a very Matlab-like syntax if you use a dot . for elementwise comparison:

julia> a = 2:7
2:7

julia> a .> 4
6-element BitArray{1}:
 false
 false
 false
  true
  true
  true

julia> a[a .> 4]
3-element Array{Int32,1}:
 5
 6
 7

Alternatively, you can call filter if you want a more functional predicate approach:

julia> filter(x -> x > 4, a)
3-element Array{Int32,1}:
 5
 6
 7