planor (version 1.5-3)

designfactors-class: Class designfactors

Description

An S4 class to represent the design factors and store their characteristics.

Objects from the Class

Objects from this class can be created explicitly by calls to planor.factors or implicitly by functions such as planor.designkey.

Slots

fact.info

a dataframe with one row per factor and with columns progressively storing information on the factors, in particular their numbers of levels (nlev).

pseudo.info

a dataframe with one row per pseudofactor and with columns progressively storing information on the pseudofactors.

levels

a list of numeric or character vectors, with each vector containing the levels of one factor.

Methods

[

extract a subset of factors and update all the slots.

bind

bind two objects. See bind method.

length

return the number of factors.

names

return the names of the factors.

Details

Depending on the context and on the construction stage, fact.info may contain logical columns that identify the block factors (block), the ordered factors (ordered), the basic factors (basic) and so on. It may also include columns that store the information on the hierarchy relationships between factors, if any.

In package planor, factors are systematically decomposed into pseudofactors which all have a prime number of levels and which play a key role in the design generation. The information on the pseudofactors is stored in the pseudo.info slot. In addition to the columns of fact.info, it contains a column (called parent) to give the factor that each pseudofactor decomposes.

See Also

Creator function: planor.factors

Examples

# NOT RUN {
F1 <- planor.factors(factors=c("block",LETTERS[1:4]), nlevels=c(6,6,4,2,6))
F2 <- planor.factors(factors=c("block",LETTERS[11:12]), nlevels=c(4,6,6))
### Method bind - a warning will be issued because two factors
### in F1 and F2 have the same name
F3 <- bind(F1,F2) 
names(F3)
length(F3)
F3@levels
F3.trt <- F3[c(2:5,7,8)]
names(F3.trt)
# }