@Override
public FieldValue evaluate(List<FieldValue> values) {
StorelessUnivariateStatistic statistic = createStatistic();
DataType dataType = null;
for (FieldValue value : values) {
// "Missing values in the input to an aggregate function are simply ignored"
if (value == null) {
continue;
}
statistic.increment((value.asNumber()).doubleValue());
if (dataType != null) {
dataType = TypeUtil.getResultDataType(dataType, value.getDataType());
} else {
dataType = value.getDataType();
}
}
if (statistic.getN() == 0) {
throw new MissingResultException(null);
}
Object result = cast(getResultType(dataType), statistic.getResult());
return FieldValueUtil.create(result);
}
@Override
public FieldValue evaluate(List<FieldValue> values) {
checkArguments(values, 1);
FieldValue value = values.get(0);
String result = evaluate(value.asString());
return FieldValueUtil.create(result);
}
@Override
public FieldValue evaluate(List<FieldValue> values) {
checkArguments(values, 1);
FieldValue value = values.get(0);
Number result = cast(getResultType(value.getDataType()), evaluate(value.asNumber()));
return FieldValueUtil.create(result);
}
@Override
public FieldValue evaluate(List<FieldValue> values) {
if (values.size() != 2) {
throw new EvaluationException();
}
FieldValue left = values.get(0);
FieldValue right = values.get(1);
// "If one of the input fields of a simple arithmetic function is a missing value, the result
// evaluates to missing value"
if (left == null || right == null) {
return null;
}
DataType dataType = TypeUtil.getResultDataType(left.getDataType(), right.getDataType());
Number result;
try {
result = evaluate(left.asNumber(), right.asNumber());
} catch (ArithmeticException ae) {
throw new InvalidResultException(null);
}
return FieldValueUtil.create(cast(dataType, result));
}