allaliases2(basis), REAL matrix basis of alias generators |

allaliases2(basis) finds the full set of aliases in a 2^(k-p) fractional factorial and returns a CHARACTER vector of these aliases as its value. k must be no larger than 25, and factors are labeled A, B, ..., H, J, ..., Z (skipping I). The p x k matrix basis contains the generators for the aliasing, one row for each generator and one column for each factor in the design. The elements in basis are 0, -1, or 1. A nonzero entry indicates that a factor is present in the generator for that row. The sign of a generator is the product of the signs of the nonzero elements of the generator. For example, 1 0 1 0 0 -1 means -ACF is a generator (alias of I). Examples: Cmd> print(b,format:"2.0f") # Matrix b is 2x5, so 2^(5-2) design b: (1,1) 1 1 1 0 0 [ABC is a generator] (2,1) 0 0 1 1 -1 [-CDE is a generator] Cmd> allaliases2(b) # alias table (1) "I = ABC = -CDE = -ABDE" (2) "A = BC = -ACDE = -BDE" (3) "B = AC = -BCDE = -ADE" (4) "AB = C = -ABCDE = -DE" (5) "D = ABCD = -CE = -ABE" (6) "AD = BCD = -ACE = -BE" (7) "BD = ACD = -BCE = -AE" (8) "ABD = CD = -ABCE = -E"

Gary Oehlert 2003-01-15