Add Algorithm: almost_equal (almostEqual) (#398)

Add floating point _almost equal_ comparison from `AMReX_Algorithm`.

src/Base/Algorithm.cpp

@@ -0,0 +1,31 @@
+/* Copyright 2021-2025 The AMReX Community
+ *
+ * Authors: Axel Huebl
+ * License: BSD-3-Clause-LBNL
+ */
+#include "pyAMReX.H"
+
+#include <AMReX_Algorithm.H>
+
+#include <type_traits>
+
+
+void init_Algorithm (py::module& m)
+{
+    using namespace amrex;
+
+    m.def(
+        "almost_equal",
+        &almostEqual<Real>,
+        py::arg("x"), py::arg("y"), py::arg("ulp")=2
+    );
+
+    if constexpr (!std::is_same_v<Real, ParticleReal>)
+    {
+        m.def(
+            "almost_equal",
+            &almostEqual<ParticleReal>,
+            py::arg("x"), py::arg("y"), py::arg("ulp")=2
+        );
+    }
+}

src/Base/CMakeLists.txt

@@ -1,6 +1,7 @@
 foreach(D IN LISTS AMReX_SPACEDIM)
     target_sources(pyAMReX_${D}d
       PRIVATE
+        Algorithm.cpp
         AMReX.cpp
         Arena.cpp
         Array4.cpp

src/pyAMReX.cpp

@@ -12,6 +12,7 @@
 
 
 // forward declarations of exposed classes
+void init_Algorithm(py::module&);
 void init_AMReX(py::module&);
 void init_Arena(py::module&);
 void init_Array4(py::module&);
@@ -90,6 +91,7 @@ PYBIND11_MODULE(amrex_3d_pybind, m) {
     init_AMReX(m);
     init_Arena(m);
     init_Dim3(m);
+    init_Algorithm(m);
     init_IntVect(m);
     init_IndexType(m);
     init_RealVect(m);