A balanced 2-spread of PG(5,2) obtained via cyclic construction
data(spreadn6t3b)The spread is formatted as a 3-dimensional array, where the [i,j,k]-th element indicates whether or not the ith basic factor is present in the jth effect of the kth flat of the spread.
The spread consists of 9 subspaces \(f_1, f_2, ..., f_9\) each of size 7. The subspaces are \(f_1=(ABC,AEF,BCEF,ADEF,BCDEF,D,ABCD)\), \(f_2 = (E,ABCEF,ABCF,BDE,BD,ACDF,ACDEF)\), \(f_3 = (DF,ABCE,ABCDEF,C,CDF,ABE,ABDEF)\), \(f_4 = (B,DEF,BDEF,AF,ABF,ADE,ABDE)\), \(f_5=(A,BDF,ABDF,ABCDE,BCDE,ACEF,CEF)\), \(f_6=(EF,AB,ABEF,ACE,ACF,BCE,BCF)\), \(f_7=(BE,F,BEF,BCDF,CDEF,BCD,CDE)\), \(f_8=(ABCDF,ADF,BC,BF,ACD,ABD,CF)\) and \(f_9=(AC,AE,CE,DE,ACDE,AD,CD)\).
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]
checkSpreadIsomorphism for checking the isomorphism of balanced spreads.
checkStarIsomorphism for checking the isomorphism of balanced covering stars.