Add a portable floating point classification API
Ceres has traditionally battled with portability issues
when trying to classify floating point values as one
type or another. For example, in C99 'isnan' is a
macro. Since it is a macro, it is impossible to
override the name in other namespaces.
Instead of trying to use preprocessor hacks to work
around the issue, define our own set of camel-case
names for use internally and by Ceres clients. For
example do this:
template<typename T>
void MyFunction(T x, T y) {
if (ceres::IsNaN(x)) {
...
}
}
instead of using "isnan" or "std::isnan". Note that
while GCC and Apple GCC both import 'isnan' into
the std namespace, it is not standard until C++11
which Ceres will not require for some years.
Change-Id: Ibcc96a8bb4ba63aa67cbbc58658b2e5671cd5824
diff --git a/internal/ceres/conjugate_gradients_solver.cc b/internal/ceres/conjugate_gradients_solver.cc
index 09a0279..7501bb2 100644
--- a/internal/ceres/conjugate_gradients_solver.cc
+++ b/internal/ceres/conjugate_gradients_solver.cc
@@ -42,6 +42,7 @@
#include <cmath>
#include <cstddef>
#include <glog/logging.h>
+#include "ceres/fpclassify.h"
#include "ceres/linear_operator.h"
#include "ceres/internal/eigen.h"
#include "ceres/types.h"
@@ -51,7 +52,7 @@
namespace {
bool IsZeroOrInfinity(double x) {
- return ((x == 0.0) || (isinf(x)));
+ return ((x == 0.0) || (IsInfinite(x)));
}
// Constant used in the MATLAB implementation ~ 2 * eps.
@@ -150,14 +151,14 @@
A->RightMultiply(p.data(), q.data());
double pq = p.dot(q);
- if ((pq <= 0) || isinf(pq)) {
+ if ((pq <= 0) || IsInfinite(pq)) {
LOG(ERROR) << "Numerical failure. pq = " << pq;
summary.termination_type = FAILURE;
break;
}
double alpha = rho / pq;
- if (isinf(alpha)) {
+ if (IsInfinite(alpha)) {
LOG(ERROR) << "Numerical failure. alpha " << alpha;
summary.termination_type = FAILURE;
break;
