Improved the tslot finder using proper ieee arithmetic routine

src/CMakeLists.txt

@@ -25,6 +25,7 @@ SET(STRICT_MATH_FILES
             ${SRC}/helio/helio_step.f90
             ${SRC}/misc/lambda_function_module.f90
             ${SRC}/misc/solver_module.f90
+            ${SRC}/netcdf_io/netcdf_io_implementations.f90  
             ${SRC}/operator/operator_module.f90
             ${SRC}/operator/operator_cross.f90
             ${SRC}/operator/operator_mag.f90
@@ -69,7 +70,6 @@ SET(FAST_MATH_FILES
             ${SRC}/encounter/encounter_io.f90
             ${SRC}/encounter/encounter_util.f90
             ${SRC}/helio/helio_util.f90
-            ${SRC}/netcdf_io/netcdf_io_implementations.f90  
             ${SRC}/rmvs/rmvs_discard.f90
             ${SRC}/rmvs/rmvs_encounter_check.f90
             ${SRC}/rmvs/rmvs_util.f90

src/netcdf_io/netcdf_io_implementations.f90

@@ -59,6 +59,8 @@ module subroutine netcdf_io_find_tslot(self, t, tslot)
       !! 
       !! Given an open NetCDF file and a value of time t, finds the index of the time value (aka the time slot) to place a new set of data.
       !! The returned value of tslot will correspond to the first index value where the value of t is greater than or equal to the saved time value.
+      use, intrinsic :: ieee_exceptions
+      use, intrinsic :: ieee_arithmetic
       implicit none
       ! Arguments
       class(netcdf_parameters), intent(inout) :: self  !! Parameters used to identify a particular NetCDF dataset
@@ -67,7 +69,10 @@ module subroutine netcdf_io_find_tslot(self, t, tslot)
       ! Internals
       real(DP), dimension(:), allocatable :: tvals
       integer(I4B) :: i
+      logical, dimension(size(IEEE_ALL))      :: fpe_halting_modes
 
+      call ieee_get_halting_mode(IEEE_ALL,fpe_halting_modes)  ! Save the current halting modes so we can turn them off temporarily
+      call ieee_set_halting_mode(IEEE_ALL,.false.)
 
       if (.not.self%lfile_is_open) return
       tslot = 0
@@ -76,7 +81,7 @@ module subroutine netcdf_io_find_tslot(self, t, tslot)
       if (self%max_tslot > 0) then
          allocate(tvals(self%max_tslot))
          call netcdf_io_check( nf90_get_var(self%id, self%time_varid, tvals(:), start=[1]), "netcdf_io_find_tslot get_var"  )
-         where(tvals(:) /= tvals(:)) tvals(:) = huge(1.0_DP)
+         where(.not.ieee_is_normal(tvals(:))) tvals(:) = huge(1.0_DP)
       else
          allocate(tvals(1))
          tvals(1) = huge(1.0_DP)
@@ -91,6 +96,8 @@ module subroutine netcdf_io_find_tslot(self, t, tslot)
       self%max_tslot = max(self%max_tslot, tslot)
       self%tslot = tslot
 
+      call ieee_set_halting_mode(IEEE_ALL,fpe_halting_modes)
+
       return
    end subroutine netcdf_io_find_tslot