getBitstrings {IsoCheck} | R Documentation |
Bitstring Representation of a Spread or Star
Description
This function computes a bitstring representation for a spread or star of PG(n-1,2)
Usage
getBitstrings(spr)
Arguments
spr |
A spread or star of |
Details
This code obtains the bitstring representation (as described in Spencer et al. 2019) for any given spread or star of PG(n-1,2)
. The spread should be formatted as a 3-dimensional array with spr[i,j,k]
indicating whether or not the i
th basic factor is present in the j
th effect of the k
th flat of spr
. This representation facilitates fast equivalence checking for spreads or stars.
Value
A matrix with each row characterizing the elements of a distinct flat in spr.
Author(s)
Neil Spencer, Pritam Ranjan, Franklin Mendivil
References
Spencer, N.A., Ranjan, P., and Mendivil, F., (2019), "Isomorphism Check for 2^n
Factorial Designs with Randomization Restrictions", Journal of Statistical Theory and Practice, 13(60),1-24 [https://doi.org/10.1007/s42519-019-0064-5]
See Also
checkSpreadEquivalence
for checking equivalence of spreads.
checkStarEquivalence
for checking equivalence of spreads.
Examples
## Example 1: The bitstring representation of a 1-spread of PG(3,2)
data(spreadn4t2a)
getBitstrings(spreadn4t2a)
## Example 2: The bitstring representation of a star of PG(4,2) consisting of 4-flats.
data(starn5t3a)
getBitstrings(starn5t3a)