1/*
2 * Copyright (C) 2016 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#import "NSArray+Extensions.h"
18
19@implementation NSArray (WALTExtensions)
20- (NSNumber *)medianValue {
21  NSArray<NSNumber *> *sorted = [self sortedArrayUsingSelector:@selector(compare:)];
22  const NSUInteger count = sorted.count;
23  if (count == 0) {
24    return nil;
25  }
26
27  if (count % 2) {
28    return [sorted objectAtIndex:count / 2];
29  } else {
30    return [NSNumber numberWithDouble:0.5 * ([sorted objectAtIndex:count / 2].doubleValue +
31                                             [sorted objectAtIndex:count / 2 - 1].doubleValue)];
32  }
33}
34@end
35