DropLowCardinality
-
class
nvtabular.ops.
DropLowCardinality
(min_cardinality=2)[source] Bases:
nvtabular.ops.operator.Operator
DropLowCardinality drops low cardinality categorical columns. This requires the cardinality of these columns to be known in the schema - for instance by first encoding these columns using Categorify.
-
transform
(col_selector: merlin.dag.selector.ColumnSelector, df: pandas.core.frame.DataFrame) → pandas.core.frame.DataFrame[source] Selects all non-categorical columns and any categorical columns of at least the minimum cardinality from the dataframe.
- Parameters
col_selector (ColumnSelector) – The columns to select.
df (DataFrameType) – The dataframe to transform
- Returns
Dataframe with only the selected columns.
- Return type
DataFrameType
-
compute_selector
(input_schema: merlin.schema.schema.Schema, selector: merlin.dag.selector.ColumnSelector, parents_selector: merlin.dag.selector.ColumnSelector, dependencies_selector: merlin.dag.selector.ColumnSelector) → merlin.dag.selector.ColumnSelector[source] Checks the cardinality of the input columns and drops any categorical columns with cardinality less than the specified minimum.
- Parameters
input_schema (Schema) – The current node’s input schema
selector (ColumnSelector) – The current node’s selector
parents_selector (ColumnSelector) – A selector for the output columns of the current node’s parents
dependencies_selector (ColumnSelector) – A selector for the output columns of the current node’s dependencies
- Returns
Selector that contains all non-categorical columns and any categorical columns of at least the minimum cardinality.
- Return type
ColumnSelector
-