precalcul

func S3v2pre ¶ added in v1.1.0

func S3v2pre(n, k, d int) *big.Int

func S3v4pre ¶ added in v1.1.0

func S3v4pre(n, k, d int) *big.Int

    Implementation of the s3 formula (read the readme section Related proposition 9 for more details)
	n - number of elements in the set
	k - number of blocks desired
	d - last element of the unranked prefix

func S3v5pre ¶ added in v1.1.0

func S3v5pre(n, k, d int) *big.Int

func UnrankDichoPre ¶

func UnrankDichoPre(n, k int, rank big.Int, vs3 int) [][]int

Unrank set partition lexicographicaly.

This function is the main function of the package and takes 4 arguments as parameters : - n : int, the cardinal of the set to be partitioned. n must be < 2000 - k : int, the number of desired blocks in the result. k must be < 2000 - rank : big.Int, the rank of the desired set partition in the lexicographical order. - whichS3: [|0,2|], the desired version of S3 formula to use (2 is the fastest, 0 is the slowest). For the time complexity, read the README section Related, theorem 12 of the article Example usage:

result := parallelunranking.UnrankDicho(5, 3, *big.NewInt(10), 4)
fmt.Println(result) // Output: [[1 2 3] [4] [5]]