Bugfix.

Signed-off-by: Daniel Scheffler <danschef@gfz-potsdam.de>

sensormapgeo/transformer_2d.py

@@ -303,10 +303,10 @@ class SensorMapGeometryTransformer(object):
         elif self.resamp_alg == 'gauss':
             # ensure that sigmas are provided as list if data is 3-dimensional
             if data.ndim != 2:
-                n_sigmas = len(opts['sigmas'])  # noqa
-
                 if not isinstance(opts['sigmas'], list):
                     opts['sigmas'] = [opts['sigmas']] * data.ndim
+
+                n_sigmas = len(opts['sigmas'])  # noqa
                 if not n_sigmas == data.ndim:
                     raise ValueError("The 'sigmas' parameter must have the same number of values like data.ndim."
                                      "n_sigmas: %d; data.ndim: %d" % (n_sigmas, data.ndim))