1package io.protobase.f7.formulas.math;
 2
 3import io.protobase.f7.errors.F7Exception;
 4import io.protobase.f7.errors.NumException;
 5import io.protobase.f7.formulas.AbstractFormula;
 6import io.protobase.f7.formulas.FormulaName;
 7import io.protobase.f7.models.GridColumnRowKey;
 8import io.protobase.f7.utils.Converters;
 9
10import java.util.function.BiFunction;
11import java.util.function.Function;
12
13public class POW extends AbstractFormula {
14  public static FormulaName NAME = FormulaName.POW;
15  public static POW SELF = new POW();
16
17  public POW() {
18    super();
19  }
20
21  public POW(Function<Object, Object> lookup, BiFunction<GridColumnRowKey, Object, Object> collateralLookup) {
22    super(lookup, collateralLookup);
23  }
24
25  @Override
26  public Object internal(GridColumnRowKey origin, Object... values) {
27    checkLength(values.length, 2, NAME);
28    Object first = Converters.first(collateralLookup.apply(origin, values[0]));
29    Object second = Converters.first(collateralLookup.apply(origin, values[1]));
30    if (first instanceof F7Exception) {
31      return first;
32    }
33    if (second instanceof F7Exception) {
34      return second;
35    }
36    double result = Math.pow(Converters.toDouble(first), Converters.toDouble(second));
37    if (Double.isNaN(result) || Double.isInfinite(result)) {
38      return new NumException("POW evaluates to an imaginary number.");
39    }
40    return result;
41  }
42}