1 // Ceres Solver - A fast non-linear least squares minimizer
2 // Copyright 2016 Google Inc. All rights reserved.
3 // http://ceres-solver.org/
5 // Redistribution and use in source and binary forms, with or without
6 // modification, are permitted provided that the following conditions are met:
8 // * Redistributions of source code must retain the above copyright notice,
9 // this list of conditions and the following disclaimer.
10 // * Redistributions in binary form must reproduce the above copyright notice,
11 // this list of conditions and the following disclaimer in the documentation
12 // and/or other materials provided with the distribution.
13 // * Neither the name of Google Inc. nor the names of its contributors may be
14 // used to endorse or promote products derived from this software without
15 // specific prior written permission.
17 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
18 // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
21 // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22 // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23 // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24 // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25 // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26 // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27 // POSSIBILITY OF SUCH DAMAGE.
29 // Authors: keir@google.com (Keir Mierle), dgossow@google.com (David Gossow)
31 #include "ceres/is_close.h"
38 bool IsClose(double x, double y, double relative_precision,
39 double *relative_error,
40 double *absolute_error) {
41 double local_absolute_error;
42 double local_relative_error;
43 if (!absolute_error) {
44 absolute_error = &local_absolute_error;
46 if (!relative_error) {
47 relative_error = &local_relative_error;
49 *absolute_error = std::fabs(x - y);
50 *relative_error = *absolute_error / std::max(std::fabs(x), std::fabs(y));
51 if (x == 0 || y == 0) {
52 // If x or y is exactly zero, then relative difference doesn't have any
53 // meaning. Take the absolute difference instead.
54 *relative_error = *absolute_error;
56 return *relative_error < std::fabs(relative_precision);
58 } // namespace internal