Because some dependencies were removed from the file requirements.txt, checks...

Because some dependencies were removed from the file requirements.txt, checks and errors have to be built in to indicate that those packages still have to be installed if one wants to make use of these modules.

lmgeo/formats/hdf5raster.py

+# Copyright (c) 2004-2021 WUR, Wageningen
 import os.path
-import re
-import tables
 from collections import Sequence
-from tables.exceptions import NoSuchNodeError
 from .raster import Raster
 from .gridenvelope2d import GridEnvelope2D
+try:
+    import tables
+    from tables.exceptions import NoSuchNodeError
+    HAS_TABLES = True
+except ImportError:
+    HAS_TABLES = False
+    raise Exception("If one wants to use the module hdf5raster, he / she needs to install Python package tables!")
 
 __author__ = "Steven B. Hoek"
 
 # Class for reading quick and dirty HDF5 format that can store weather data
 # in a raster format in an efficient way, for fast access
 class Hdf5Raster(Raster, GridEnvelope2D):
-    "A raster represented by 2 files, with extensions 'h5' and 'hdr'"
+    '''A raster represented by 2 files, with extensions "h5" and "hdr"'''
     
     # Constants
     DATAFILEXT = "h5";
@@ -45,7 +50,13 @@ class Hdf5Raster(Raster, GridEnvelope2D):
         dataset_name="dummy", group_prefix="row", table_prefix="col", index_format="04i", variables=[], units=[]):
         # Initialise
         super(Hdf5Raster, self).open(mode);
-        fpath = os.path.join(self.folder, self.name);
+        fpath = os.path.join(self.folder, self.name)
+        
+        # Raise error again if Python package tables is not installed
+        if not HAS_TABLES:
+            raise Exception("If one wants to use the module hdf5raster, he / she needs to install Python package tables!")
+        
+        # Now prepare to read from file or to write it
         if (mode[0] == 'w'):
             # Open the file
             self.datafile = tables.open_file(fpath, 'w');

lmgeo/formats/netcdf4raster.py

-# Copyright (c) 2004-2020 WUR, Wageningen
-from .netcdf4envelope2d import Netcdf4Envelope2D;
-from .gridenvelope2d import GridEnvelope2D;
-from netCDF4 import Dataset;
-import os;
+# Copyright (c) 2004-2021 WUR, Wageningen
+from .netcdf4envelope2d import Netcdf4Envelope2D
+from .gridenvelope2d import GridEnvelope2D
+import os
+try:
+    from netCDF4 import Dataset
+    HAS_NETCDF4 = True
+except ImportError:
+    HAS_NETCDF4 = False
+    raise Exception("If one wants to use the module netcdf4raster, he / she needs to install Python package netCDF4!")
 
 __author__ = "Steven B. Hoek"
 
@@ -35,6 +40,12 @@ class Netcdf4Raster(Netcdf4Envelope2D):
     def open(self, mode, ncols=1, nrows=1, xll=0, yll=0, cellsize=1, nodatavalue=-9999.0):
         # If file does not exist and mode[0] = 'w', create it!
         fpath = os.path.join(self.folder, self.name);
+        
+        # Raise error again if netCDF4 is not installed
+        if not HAS_NETCDF4:
+            raise Exception("If one wants to use the module netcdf4raster, he / she needs to install Python package netCDF4!")
+        
+        # Now prepare to read from file or to write it
         if mode[0] == 'a':
             if os.path.exists(fpath):
                 print("About to open file " + fpath + " in append mode");

lmgeo/formats/numpyraster.py

 # Copyright (c) 2004-2021 WUR, Wageningen
 import os.path
-import numpy as np
 from .raster import Raster
 from .gridenvelope2d import GridEnvelope2D
 from .const import constants as const
+try:
+    import numpy as np
+    HAS_NUMPY = True
+except ImportError:
+    HAS_NUMPY = False
+    raise Exception("If one wants to use the module numpyraster, he / she needs to install Python package numpy!")
 
 __author__ = "Steven B. Hoek"
 
@@ -34,6 +39,11 @@ class NumpyRaster(Raster, GridEnvelope2D):
     def open(self, mode, ncols=1, nrows=1, xll=0., yll=0., cellsize=1., nodatavalue=-9999.0):
         super(NumpyRaster, self).open(mode);
         fpath = os.path.join(self.folder, self.name)
+        
+        # Raise error again if numpy is not installed
+        if not HAS_NUMPY:
+            raise Exception("If one wants to use the module numpyraster, he / she needs to install Python package numpy!")
+        
         if (mode[0] == 'w'):
             # Open the file
             self.datafile = None