The precision_by variables are used to collect the integer and decimal precision when auto-precision is used. These by variables are used to group the input data and identify the maximum precision available within the dataset for each by group. The precision_by variables must be a subset of the by variables
get_precision_by(layer) set_precision_by(layer, precision_by)
A string, a variable name, or a list of variable names supplied
get_precision_by, the precision_by binding of the supplied
set_precision_by the modified layer environment.