proj_inv_xyvals: check result for NaNs.

NEWS

@@ -5,6 +5,8 @@ Improvement
 
 Version 1.9.10 (29 January 2021):
 
+   New features:
+     * Added option --ignore_time_bounds to ignore time bounds for time range statistics
    Fixed bugs:
      * timselmean: failed with variables on different grids [Bug #9978]
      * Ymonarith: failed with variables on different grids

src/mpim_grid/grid_proj.cc

@@ -73,29 +73,36 @@ gen_param(const char *fmt, ...)
 static void
 proj_fwd_xyvals(PJ *proj, size_t nvals, double *xvals, double *yvals)
 {
+  size_t num_nans = 0;
   PJ_COORD p;
   for (size_t i = 0; i < nvals; i++)
     {
       p.uv.u = proj_torad(xvals[i]);
       p.uv.v = proj_torad(yvals[i]);
       p = proj_trans(proj, PJ_FWD, p);
+      if (std::isnan(p.uv.u) || std::isnan(p.uv.v)) num_nans++;
       xvals[i] = p.uv.u;
       yvals[i] = p.uv.v;
     }
+  if (num_nans) cdoWarning("%s: %zu of %zu projection coodinates are NaN!", __func__, num_nans, 2*nvals);
 }
 
 static void
 proj_inv_xyvals(PJ *proj, size_t nvals, double *xvals, double *yvals)
 {
+  size_t num_nans = 0;
   PJ_COORD p;
   for (size_t i = 0; i < nvals; i++)
     {
       p.uv.u = xvals[i];
       p.uv.v = yvals[i];
       p = proj_trans(proj, PJ_INV, p);
+      if (std::isnan(p.uv.u) || std::isnan(p.uv.v)) num_nans++;
       xvals[i] = proj_todeg(p.uv.u);
       yvals[i] = proj_todeg(p.uv.v);
     }
+  if (num_nans) cdoWarning("%s: %zu of %zu projection coodinates are NaN!", __func__, num_nans, 2*nvals);
+
 }
 
 static int