call:The (matched) function call.
prior:Prior probabilities used, default to group proportions
counts:number of observations in each class
center:the group means
cov:the common covariance matrix
ldf:a matrix containing the linear discriminant functions
ldfconst:a vector containing the constants of each linear discriminant function
method:a character string giving the estimation method used
X:the training data set (same as the input parameter x of the constructor function)
grp:grouping variable: a factor specifying the class for each observation.