How to extract other than a specific index with Numpy

It is a method to extract other than a specific index from an array.

# 0~Randomly fetch 10 from the number 99
arr = np.random.randint(0, 100, 10)
# > array([74, 29,  6, 79, 76, 13,  3, 56, 25, 50])

#I want to exclude odd-numbered numbers from arr
odd = [1,3,5,7,9]

#Method ① List comprehension
index = [i for i in np.arange(len(arr)) if i not in odd]
arr_even = arr[index]

#Method ② True/Mask with False
index = np.ones(len(arr), dtype=bool)
index[odd] = False
arr_even = arr[index]

#Method ③ np.delete
arr_even = np.delete(arr, odd)

Method ③ is the most refreshing, but it doesn't change much in terms of time, so please use your favorite method.

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