Check if an Element is in Array in Julia

Check if an Element is in Array in Julia

  • Julia
  • 2 mins read

To check if an element is in an array in Julia, you can use the in keyword. Here's an example:

Check if an Element is in Array in Julia Examples

In the example below, the in keyword is used to check if the element 3 is in the array a. Since 3 is in the array, the expression 3 in a returns true.

julia> a = [1, 2, 3, 4, 5]
julia> 3 in a
true

Here's another example:

In this example, the in keyword is used to check if the element 3 is in the array b. Since 3 is not in the array, the expression 3 in b returns false.

julia> b = [6, 7, 8, 9, 10]
julia> 3 in b
false

Note that the in keyword can only be used to check if an element is in an array. It cannot be used to check if an element is in other types of collections, such as sets or dictionaries. To check if an element is in a set or dictionary, you can use the in keyword along with the keys or values function, depending on what you're looking for.

In the examples below, the in keyword is used with the values function to check if the element 3 is a key in the set s, and with the values function to check if the element 3 is a value in the dictionary d. Since 3 is a key in s and a value in d, the expressions 3 in keys(s) and 3 in values(d) both return true.

julia> s = Set([1, 2, 3, 4, 5])
julia> 3 in values(s)
true

julia> d = Dict(1 => "one", 2 => "two", 3 => "three")
julia> 3 in values(d)
true

Related:

  1. Check if a File Exists in Julia
  2. Check if a Variable Exists in Julia
  3. Check if a Key is in Dictionary using Julia