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randsubseq

randsubseq(A, p) -> Vector

Return a vector consisting of a random subsequence of the given array A, where each element of A is included (in order) with independent probability p. (Complexity is linear in p*length(A), so this function is efficient even if p is small and A is large.) Technically, this process is known as "Bernoulli sampling" of A.

Examples

1. Generate a random subsequence of an array:

   julia> arr = [1, 2, 3, 4, 5];
   julia> randsubseq(arr, 0.5)
   2-element Array{Int64,1}:
   3
   4

   This example generates a random subsequence of the array arr with each element being included with an independent probability of 0.5.

2. Create a random subset of strings:

   julia> words = ["apple", "banana", "orange", "grape"];
   julia> randsubseq(words, 0.3)
   1-element Array{String,1}:
   "orange"

   It generates a random subsequence of the vector of strings words with each element being included with an independent probability of 0.3.

3. Generate a shuffled version of an array:

   julia> numbers = [1, 2, 3, 4, 5];
   julia> randsubseq(numbers, 1.0)
   5-element Array{Int64,1}:
   1
   5
   4
   3
   2

   It generates a shuffled version of the array numbers where each element is included with a probability of 1.0.

Common mistake example:

julia> arr = [1, 2, 3, 4, 5];
julia> randsubseq(arr, 1.5)
ERROR: DomainError with 1.5:
Value must be in the range [0, 1]

In this example, an invalid probability value of 1.5 is provided. The probability p should be in the range [0, 1]. Make sure to provide a valid probability value to avoid such errors.

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