PivotTableTest.java

package tech.tablesaw.aggregate;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertTrue;

import org.junit.jupiter.api.Test;
import tech.tablesaw.api.Table;
import tech.tablesaw.io.csv.CsvReadOptions;

public class PivotTableTest {

  @Test
  public void pivot() throws Exception {
    Table t =
        Table.read()
            .csv(CsvReadOptions.builder("../data/bush.csv").missingValueIndicator(":").build());
    t.addColumns(t.dateColumn("date").year());

    Table pivot =
        PivotTable.pivot(
            t,
            t.categoricalColumn("who"),
            t.categoricalColumn("date year"),
            t.numberColumn("approval"),
            AggregateFunctions.mean);
    assertTrue(pivot.columnNames().contains("who"));
    assertTrue(pivot.columnNames().contains("2001"));
    assertTrue(pivot.columnNames().contains("2002"));
    assertTrue(pivot.columnNames().contains("2003"));
    assertTrue(pivot.columnNames().contains("2004"));
    assertEquals(6, pivot.rowCount());
  }
}