tech.tablesaw.mapping.LongMapUtils 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.mapping;
import tech.tablesaw.api.FloatColumn;
import tech.tablesaw.api.LongColumn;
import tech.tablesaw.columns.Column;
import tech.tablesaw.columns.LongColumnUtils;
public interface LongMapUtils extends LongColumnUtils {
default LongColumn plus(LongColumn... columns) {
// TODO(lwhite): Assert all columns are the same size.
String nString = names(columns);
String name = String.format("sum(%s)", nString);
LongColumn newColumn = new LongColumn(name);
for (int r = 0; r < columns[0].size(); r++) {
long result = 0;
for (LongColumn column : columns) {
result = result + column.get(r);
}
newColumn.append(result);
}
return newColumn;
}
// TODO(lwhite): make this a shared utility
default String names(LongColumn[] columns) {
StringBuilder builder = new StringBuilder();
int count = 0;
for (Column column : columns) {
builder.append(column.name());
if (count < columns.length - 1) {
builder.append(", ");
}
count++;
}
return builder.toString();
}
/**
* Return the elements of this column as the ratios of their value and the sum of all
* elements
*/
default FloatColumn asRatio() {
FloatColumn pctColumn = new FloatColumn(name() + " percents");
float total = sum();
for (long next : this) {
if (total != 0) {
pctColumn.append((float) next / total);
} else {
pctColumn.append(FloatColumn.MISSING_VALUE);
}
}
return pctColumn;
}
/**
* Return the elements of this column as the percentages of their value relative to the sum of all
* elements
*/
default FloatColumn asPercent() {
FloatColumn pctColumn = new FloatColumn(name() + " percents");
float total = sum();
for (long next : this) {
if (total != 0) {
pctColumn.append(((float) next / total) * 100);
} else {
pctColumn.append(FloatColumn.MISSING_VALUE);
}
}
return pctColumn;
}
long sum();
long get(int index);
default LongColumn difference(LongColumn column2) {
LongColumn result = new LongColumn(name() + " - " + column2.name(), size());
for (int r = 0; r < size(); r++) {
result.append(get(r) - column2.get(r));
}
return result;
}
}