package org.basex.query.func.math;

import static java.lang.StrictMath.*;

import org.basex.query.*;
import org.basex.query.func.*;
import org.basex.query.value.item.*;
import org.basex.util.*;

/**
 * Function implementation.
 *
 * @author BaseX Team 2005-18, BSD License
 * @author Christian Gruen
 */
public final class MathSqrt extends StandardFunc {
  @Override
  public Item item(final QueryContext qc, final InputInfo ii) throws QueryException {
    final Item item = exprs[0].atomItem(qc, info);
    return item == null ? null : Dbl.get(sqrt(toDouble(item)));
  }
}
