tech.tablesaw.table.Rows Maven / Gradle / Ivy
/*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package tech.tablesaw.table;
import tech.tablesaw.api.ColumnType;
import tech.tablesaw.api.Table;
import tech.tablesaw.columns.Column;
import tech.tablesaw.selection.BitmapBackedSelection;
import tech.tablesaw.selection.Selection;
import javax.annotation.concurrent.Immutable;
/**
* A static utility class for row operations
*/
@Immutable
public final class Rows {
// Don't instantiate
private Rows() {}
/**
* Copies the rows indicated by the row index values in the given selection from oldTable to newTable
*/
@SuppressWarnings({"rawtypes","unchecked"})
public static void copyRowsToTable(Selection rows, Table oldTable, Table newTable) {
for (int columnIndex = 0; columnIndex < oldTable.columnCount(); columnIndex++) {
Column oldColumn = oldTable.column(columnIndex);
int r = 0;
for (int i : rows) {
newTable.column(columnIndex).set(r, oldColumn, i);
r++;
}
}
}
/**
* Copies the rows indicated by the row index values in the given array from oldTable to newTable
*/
@SuppressWarnings({"rawtypes","unchecked"})
public static void copyRowsToTable(int[] rows, Table oldTable, Table newTable) {
for (int columnIndex = 0; columnIndex < oldTable.columnCount(); columnIndex++) {
Column oldColumn = oldTable.column(columnIndex);
int r = 0;
for (int i : rows) {
newTable.column(columnIndex).set(r, oldColumn, i);
r++;
}
}
}
@SuppressWarnings({"rawtypes","unchecked"})
public static void appendRowToTable(int row, Table oldTable, Table newTable) {
int[] rows = new int[] {row};
for (int columnIndex = 0; columnIndex < oldTable.columnCount(); columnIndex++) {
Column oldColumn = oldTable.column(columnIndex);
for (int i : rows) {
newTable.column(columnIndex).append(oldColumn, i);
}
}
}
public static boolean compareRows(int rowInOriginal, Table original, Table tempTable) {
int columnCount = original.columnCount();
boolean result;
for (int columnIndex = 0; columnIndex < columnCount; columnIndex++) {
ColumnType columnType = original.column(columnIndex).type();
result = columnType.compare(rowInOriginal, tempTable.column(columnIndex), original.column(columnIndex));
if (!result) {
return false;
}
}
return true;
}
public static void head(int rowCount, Table oldTable, Table newTable) {
Selection rows = new BitmapBackedSelection(rowCount);
for (int i = 0; i < rowCount; i++) {
rows.add(i);
}
copyRowsToTable(rows, oldTable, newTable);
}
public static void tail(int rowsToInclude, Table oldTable, Table newTable) {
int oldTableSize = oldTable.rowCount();
int start = oldTableSize - rowsToInclude;
Selection rows = new BitmapBackedSelection(rowsToInclude);
for (int i = start; i < oldTableSize; i++) {
rows.add(i);
}
copyRowsToTable(rows, oldTable, newTable);
}
}