consider difference in plev key value

pcmdi_metrics/mean_climate/lib/load_and_regrid.py

@@ -58,9 +58,27 @@ def load_and_regrid(data_path, varname, varname_in_file=None, level=None, t_grid
  if 'plev' in list(ds.coords.keys()):
  if ds.plev.units == 'Pa':
  level = level * 100 # hPa to Pa
- ds = ds.sel(plev=level)
+ try:
+ ds = ds.sel(plev=level)
+ except Exception as ex:
+ print('WARNING: ', ex)
+
+ nearest_level = find_nearest(ds.plev.values, level)
+
+ print(' Given level', level)
+ print(' Selected nearest level from dataset:', nearest_level)
+
+ diff_percentage = abs(nearest_level - level) / level * 100
+ if diff_percentage < 0.1: # acceptable if differance is less than 0.1%
+ ds = ds.sel(plev=level, method='nearest')
+ print(' Difference is in acceptable range.')
+ pass
+ else:
+ print('ERROR: Difference between two levels are too big!')
+ return
  if debug:
  print('ds:', ds)
+ print('ds.plev.units:', ds.plev.units)
  else:
  print('ERROR: plev is not in the nc file. Check vertical coordinate.')
  print('Coordinates keys in the nc file:', list(ds.coords.keys()))
@@ -90,3 +108,10 @@ def load_and_regrid(data_path, varname, varname_in_file=None, level=None, t_grid
  if debug:
  print('ds_regridded:', ds_regridded)
  return ds_regridded
+
+
+def find_nearest(array, value):
+ array = np.asarray(array)
+ idx = (np.abs(array - value)).argmin()
+ return array[idx]
+