splitBy builds a training set and validation set by placing
all samples that have the include annotation in the specified
colBy column in the training set. The remaining samples get
placed in the validation set. This split is not random.
splitBy(object, colBy, include)An ExprsArray object to split.
A character string. Specifies the column used to split the data.
A character vector. Specifies which annotations in colBy
to include in the training set.
Returns a list of two ExprsArray objects.