Squashed 'third_party/ceres/' content from commit e51e9b4
Change-Id: I763587619d57e594d3fa158dc3a7fe0b89a1743b
git-subtree-dir: third_party/ceres
git-subtree-split: e51e9b46f6ca88ab8b2266d0e362771db6d98067
diff --git a/internal/ceres/is_close.cc b/internal/ceres/is_close.cc
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+// Ceres Solver - A fast non-linear least squares minimizer
+// Copyright 2016 Google Inc. All rights reserved.
+// http://ceres-solver.org/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// * Redistributions of source code must retain the above copyright notice,
+// this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above copyright notice,
+// this list of conditions and the following disclaimer in the documentation
+// and/or other materials provided with the distribution.
+// * Neither the name of Google Inc. nor the names of its contributors may be
+// used to endorse or promote products derived from this software without
+// specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+// POSSIBILITY OF SUCH DAMAGE.
+//
+// Authors: keir@google.com (Keir Mierle), dgossow@google.com (David Gossow)
+
+#include "ceres/is_close.h"
+
+#include <algorithm>
+#include <cmath>
+
+namespace ceres {
+namespace internal {
+bool IsClose(double x, double y, double relative_precision,
+ double *relative_error,
+ double *absolute_error) {
+ double local_absolute_error;
+ double local_relative_error;
+ if (!absolute_error) {
+ absolute_error = &local_absolute_error;
+ }
+ if (!relative_error) {
+ relative_error = &local_relative_error;
+ }
+ *absolute_error = std::fabs(x - y);
+ *relative_error = *absolute_error / std::max(std::fabs(x), std::fabs(y));
+ if (x == 0 || y == 0) {
+ // If x or y is exactly zero, then relative difference doesn't have any
+ // meaning. Take the absolute difference instead.
+ *relative_error = *absolute_error;
+ }
+ return *relative_error < std::fabs(relative_precision);
+}
+} // namespace internal
+} // namespace ceres