Package tech.tablesaw.table

Class TableSliceGroup

java.lang.Object
tech.tablesaw.table.TableSliceGroup
All Implemented Interfaces:
Iterable<TableSlice>
Direct Known Subclasses:
SelectionTableSliceGroup, StandardTableSliceGroup
public abstract class TableSliceGroup extends Object implements Iterable<TableSlice>
A group of virtual tables (table slices) formed by performing splitting operations on an original table See: TableSlice

  • Field Details

    • SPLIT_STRING

      protected static final String SPLIT_STRING
      A string that is used internally as a delimiter in creating a column name from all the grouping columns
      See Also:

  • Constructor Details

    • TableSliceGroup

      protected TableSliceGroup(Table original)
      Returns an instance for calculating a single summary for the given table, with no sub-groupings

    • TableSliceGroup

      protected TableSliceGroup(Table sourceTable, String[] groupColumnNames)
      Returns an instance for calculating subgroups, one for each combination of the given groupColumnNames that appear in the source table

  • Method Details

    • getSplitColumnNames

      protected String[] getSplitColumnNames()
      Returns the names of the columns the backing table was split on.

    • getByteSize

      protected int getByteSize(List<Column<?>> columns)
      Returns the sum of the sizes for the columns in the given Column list

    • addSlice

      protected void addSlice(TableSlice slice)
      Add a slice to this group

    • getSlices

      public List<TableSlice> getSlices()
      Returns the slices as a list

    • get

      public TableSlice get(int i)
      Returns the ith slice in this group

    • getSourceTable

      public Table getSourceTable()
      Returns the table behind this slice group

    • size

      public int size()
      Returns the number of slices

    • aggregate

      public Table aggregate(String colName1, AggregateFunction<?,?>... functions)
      Applies the given aggregation to the given column. The apply and combine steps of a split-apply-combine.

    • aggregate

      public Table aggregate(com.google.common.collect.ListMultimap<String,AggregateFunction<?,?>> functions)
      Applies the given aggregations to the given columns. The apply and combine steps of a split-apply-combine.
      Parameters:
      functions - map from column name to aggregation to apply on that function

    • summaryTableName

      public static Table summaryTableName(Table source)
      Returns the name of a summary table made by aggregating on the slices in this group

    • iterator

      public Iterator<TableSlice> iterator()
      Returns an iterator over elements of type T.
      Specified by:
      iterator in interface Iterable<TableSlice>
      Returns:
      an Iterator.

    • aggregateColumnName

      public static String aggregateColumnName(String columnName, String functionName)
      Returns a column name for aggregated data based on the given source column name and function

    • asTableList

      public List<Table> asTableList()
      Returns a list of Tables created by reifying my list of slices (views) over the original table

    • setSourceTable

      protected void setSourceTable(Table sourceTable)
      Sets the source table that backs this TableSliceGroup