PageRenderTime 12ms CodeModel.GetById 9ms app.highlight 1ms RepoModel.GetById 1ms app.codeStats 1ms

/tags/release-0.0.0-rc0/hive/external/ql/src/java/org/apache/hadoop/hive/ql/udf/UDFAsin.java

#
Java | 53 lines | 23 code | 6 blank | 24 comment | 3 complexity | 6db2e3b9aa1a5918aef966340c885929 MD5 | raw file
 1/**
 2 * Licensed to the Apache Software Foundation (ASF) under one
 3 * or more contributor license agreements.  See the NOTICE file
 4 * distributed with this work for additional information
 5 * regarding copyright ownership.  The ASF licenses this file
 6 * to you under the Apache License, Version 2.0 (the
 7 * "License"); you may not use this file except in compliance
 8 * with the License.  You may obtain a copy of the License at
 9 *
10 *     http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
17 */
18
19package org.apache.hadoop.hive.ql.udf;
20
21import org.apache.hadoop.hive.ql.exec.Description;
22import org.apache.hadoop.hive.ql.exec.UDF;
23import org.apache.hadoop.hive.serde2.io.DoubleWritable;
24
25/**
26 * UDFAsin.
27 *
28 */
29@Description(name = "asin",
30    value = "_FUNC_(x) - returns the arc sine of x if -1<=x<=1 or NULL otherwise",
31    extended = "Example:\n"
32    + "  > SELECT _FUNC_(0) FROM src LIMIT 1;\n"
33    + "  0\n"
34    + "  > SELECT _FUNC_(2) FROM src LIMIT 1;\n" + "  NULL")
35public class UDFAsin extends UDF {
36  private DoubleWritable result = new DoubleWritable();
37
38  public UDFAsin() {
39  }
40
41  /**
42   * Take Arc Sine of a in radians.
43   */
44  public DoubleWritable evaluate(DoubleWritable a) {
45    if (a == null) {
46      return null;
47    } else {
48      result.set(Math.asin(a.get()));
49      return result;
50    }
51  }
52
53}