Usage
partLm(x1, y1, alpha = 0.1, lambda = 1, lambda.seq = NULL,
part.minsplit = 2, part.xval = 0, part.max.depth = 1,
part.cp = 0, part.minbucket = 5, minobsinnode.lin = 5,
lin.type = "glmnet", cv.glmnet.nfolds = 5,
cv.glmnet.lambda = "lambda.min", verbose = TRUE, trace = 0)