/src/h3/src/h3lib/lib/mathExtensions.c
Line | Count | Source (jump to first uncovered line) |
1 | | /* |
2 | | * Copyright 2017 Uber Technologies, Inc. |
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 | | /** @file mathExtensions.c |
17 | | * @brief Math functions that should've been in math.h but aren't |
18 | | */ |
19 | | |
20 | | #include "mathExtensions.h" |
21 | | |
22 | | /** |
23 | | * _ipow does integer exponentiation efficiently. Taken from StackOverflow. |
24 | | * |
25 | | * @param base the integer base (can be positive or negative) |
26 | | * @param exp the integer exponent (should be nonnegative) |
27 | | * |
28 | | * @return the exponentiated value |
29 | | */ |
30 | 0 | int64_t _ipow(int64_t base, int64_t exp) { |
31 | 0 | int64_t result = 1; |
32 | 0 | while (exp) { |
33 | 0 | if (exp & 1) result *= base; |
34 | 0 | exp >>= 1; |
35 | 0 | base *= base; |
36 | 0 | } |
37 | |
|
38 | 0 | return result; |
39 | 0 | } |