I have this array :
>> arr = [["a",1,"b"],["a",2,"b"],["b",3,"d"],["t",6,"a"]]
I want to check if ["a",1] exists inside the arr while ignoring the 3rd value of the arr items.
Is there a better way then first removing the 3rd value from each item in arr:
>> new_arr = [["a",1],["a",2],["b",3],["t",6]]
and then doing
>> new_arr.include? ["a",1]
true
Something like:
arr.include? ["a",1,/*/] #the 3rd value can be anything
Thanks.
You can try the below :
arr = [["a",1,"b"],["a",2,"b"],["b",3,"d"],["t",6,"a"]]
arr.any? { |v1, v2, *| [v1, v2] == ["a", 1] }
# => true
arr.any? { |v1, v2, *| [v1, v2] == ["a", 4] }
# => false
wrap the logic inside a method :
def check_subarray(ary, sub_ary)
ary.any? { |e1, e2, *| [e1, e2] == sub_ary }
end
arr = [["a",1,"b"],["a",2,"b"],["b",3,"d"],["t",6,"a"]]
check_subarray(arr, ["a", 1]) # => true
Here's a more complicated version of @Arup's answer (it handles arbitrary lengths, though)
def match_head(*head)
->(full_array) {
head.each_with_index do |head_elem, idx|
return false if full_array[idx] != head_elem
end
true
}
end
ary = [["a",1,"b"],["a",2,"b"],["b",3,"d"],["t",6,"a"]]
ary.any?(&match_head('a')) # => true
ary.any?(&match_head('c')) # => false
ary.any?(&match_head('a', 1)) # => true
ary.any?(&match_head('a', 1, 'b')) # => true
ary.any?(&match_head('a', 1, 'f')) # => false
Another way:
def values_there?(arr, val)
arr.transpose[0,val.size].transpose.include? val
end
values_there?(arr, ["a", 2]) #=> true
values_there?(arr, [3, "d"]) #=> false