When using Data to assign a data.frame to the Data slot in the
"xpose.data" object a number of things happen:
Each column in the data.frame is checked and set to factor if
the number of unique values are less than the value of
Cat.levels (see xpose.prefs-class
).
It is checked which of the predefined xpose data
variables that exists in the data.frame. The variable defintions that
does not exist are set to NULL.
The column identified by the dv
xpose variable definition, is
checked and set to factor if the number of unique values are less than
or equal to the DV.Cat.levels (see xpose.prefs-class
).
Finally, each column name in the data.frame is checked for a label
(see xpose.prefs-class
). If it is non-existent, the
label is set to the column name.
When SData is used to assign a data.frame to the SData slot it is
first checked that the number of rows in the SData data.frame is an
even multiple of the number of rown in Data. Next, each column in the
SData data.frame is assigned the same class as the corresponding
column in the Data data.frame (it is required that the columns are the
same in Data and SData). Finally, an extra column, "iter", is added to SData,
which indicates the iteration number that each row belongs to. At the
same time, the Nsim slot of the "xpose.data" object is set to the
number of iterations (see nsim
).