fac.design
fac.design object, with factors, blocks and
center points as designated.
as.fac.design(x, factors = seq(length(x)),
block = F, cpoints = F)
read.table.
x to use as factors. Can be
vector of column numbers or names.
"Quad", which
distinguishes design points from center points.
fac.design.
The functions
fac.aov and
plot.design rely on the data having
attributes of the class
fac.design. When the experiment is read from
an external file, a user can use
as.fac.design to interface easily
to the fractional factorial functions of the S+DOX module.
If
cpoints are designated, an extra, non-printing variable,
Quad,
is added to the returned
fac.design. This factor is used by
formula.fac.design
to fit a quadratic term, testing center points
versus design points, in the model fit by
fac.aov.
Avoid using factor names
F and
T as these can get confused with
FALSE
and
TRUE. The default factor names skips these two letters.
raw.data <- read.table(file="myfile.txt",header=T) data.design <- as.fac.design(raw.data, 1:4)