Search for a design key or a collection of design keys that satisfy the design properties specified by the arguments. This function implements the core algorithms of the planor package.
planor.designkey(factors, nlevels, block, ordered, hierarchy, model,
estimate, listofmodels, resolution, nunits, base, max.sol=1,
randomsearch=FALSE, verbose=TRUE)an object of class '>designfactors,
typically an output from
planor.factors. Alternatively, you can use
the arguments factors, nlevels, ordered,
hierarchy as described in the syntax of planor.factors.
see planor.factors. Ignored if
factors is of class '>designfactors.
see planor.factors. Ignored if
factors is of class '>designfactors.
see planor.factors. Ignored if
factors is of class '>designfactors.
see planor.factors. Ignored if
factors is of class '>designfactors.
a list of model-estimate pairs of formulae, typically an
output from planor.model. Alternatively, you can use
the arguments
model, estimate, listofmodels and
resolution, as described in the syntax of
planor.model.
see planor.model. Ignored if
model is a list.
see planor.model. Ignored if
model is a list.
see planor.model. Ignored if
model is a list. When set and there is no hierarchy, a faster algorithm is used
which exploits the symmetries.
a scalar giving the total number of units in the design
an optional additive formula to specify the basic factors. See Note.
maximum number of solutions before exit.
a logical. If TRUE, the searches for a key
matrix are performed in a random order.
a logical to set to TRUE for verbose
display.
An object of class '>listofkeyrings in most
cases. Otherwise, i.e in recursive cases, an object of class
'>listofdesignkeys.
The methods implemented in planor rely on a decomposition of the design search according to prime numbers. The prime numbers involved are those that decompose the numbers of levels of the factors. For example, if all factors have 2, 4, or 8 levels, then the number of units must be a power of 2 and the only prime number involved is 2. This is called the symmetric case. But if at least one factor has 6 levels, or if factor \(A\) has 2 levels and factor \(B\) has 3 levels, then the number of units must be the product of a power of 2 by a power of 3. In this case the search is automatically decomposed into one for prime 2 and one for prime 3. This is called the asymmetric case.
In the symmetric case with prime \(p\), a regular factorial design
requires a single key matrix of integers modulo \(p\). In the
asymmetric case, it requires one key matrix per prime. In
planor, key matrices are stored in objects of class
'>keymatrix. The lists made of one key matrix per
prime are called design keys. They are stored in objects of class
'>designkey.
The function planor.designkey essentially searches for
design keys that satisfy the user specifications. For technical
reasons, however, its output can take two different forms: either an
object of class '>listofkeyrings or an object of
class '>listofdesignkeys. The function
planor.designkey detects automatically which case
applies. In the first case (independent case), the key matrix
solutions can be searched independently between primes and they are
stored in objects of class '>listofkeyrings. The
second case (recursive case) occurs exceptionnally. In that
case the search cannot be independent between primes and so the
different solutions are directly stored in a list of class
'>listofdesignkeys.
planor.factors, planor.model, and
the classes '>designfactors,
'>listofkeyrings,
'>listofdesignkeys
# NOT RUN {
K0 <- planor.designkey(factors=c("block", LETTERS[1:4]),
nlevels=rep(3,5), model=~block+(A+B+C+D)^2, estimate=~A+B+C+D,
nunits=3^3, base=~A+B+C, max.sol=2)
### With automatic model generation
Km <- planor.designkey(factors=c("block", LETTERS[1:4]),
nlevels=rep(2,5), resolution=3, nunits=2^4)
# }
Run the code above in your browser using DataLab