[Draft] seed: use Ellipsis to indicate keeping current seed

.gitignore

@@ -45,6 +45,7 @@ nosetests.xml
 coverage.xml
 *.cover
 .hypothesis/
+cov.xml
 
 # Translations
 *.mo

src/gstools/field/cond_srf.py

@@ -64,7 +64,7 @@ def __init__(self, krige, generator="RandMeth", **generator_kwargs):
     def __call__(
         self,
         pos=None,
-        seed=np.nan,
+        seed=...,
         mesh_type="unstructured",
         post_process=True,
         store=True,
@@ -80,8 +80,10 @@ def __call__(
         pos : :class:`list`, optional
             the position tuple, containing main direction and transversal
             directions
-        seed : :class:`int`, optional
-            seed for RNG for resetting. Default: keep seed from generator
+        seed : :class:`int` or :any:`None` or :any:`Ellipsis`, optional
+            the seed of the random number generator.
+            If :any:`None`, a random seed is used. If :any:`Ellipsis`,
+            the current seed will be kept. Default: :any:`Ellipsis`
         mesh_type : :class:`str`
             'structured' / 'unstructured'
         post_process : :class:`bool`, optional

src/gstools/field/generator.py

@@ -52,7 +52,7 @@ def __init__(self, model, **kwargs):
         pass
 
     @abstractmethod
-    def update(self, model=None, seed=np.nan):
+    def update(self, model=None, seed=...):
         """Update the model and the seed.
 
         If model and seed are not different, nothing will be done.
@@ -61,10 +61,10 @@ def update(self, model=None, seed=np.nan):
         ----------
         model : :any:`CovModel` or :any:`None`, optional
             covariance model. Default: :any:`None`
-        seed : :class:`int` or :any:`None` or :any:`numpy.nan`, optional
+        seed : :class:`int` or :any:`None` or :any:`Ellipsis`, optional
             the seed of the random number generator.
-            If :any:`None`, a random seed is used. If :any:`numpy.nan`,
-            the actual seed will be kept. Default: :any:`numpy.nan`
+            If :any:`None`, a random seed is used. If :any:`Ellipsis`,
+            the current seed will be kept. Default: :any:`Ellipsis`
         """
 
     @abstractmethod
@@ -235,7 +235,7 @@ def get_nugget(self, shape):
             nugget = 0.0
         return nugget
 
-    def update(self, model=None, seed=np.nan):
+    def update(self, model=None, seed=...):
         """Update the model and the seed.
 
         If model and seed are not different, nothing will be done.
@@ -244,33 +244,30 @@ def update(self, model=None, seed=np.nan):
         ----------
         model : :any:`CovModel` or :any:`None`, optional
             covariance model. Default: :any:`None`
-        seed : :class:`int` or :any:`None` or :any:`numpy.nan`, optional
+        seed : :class:`int` or :any:`None` or :any:`Ellipsis`, optional
             the seed of the random number generator.
-            If :any:`None`, a random seed is used. If :any:`numpy.nan`,
-            the actual seed will be kept. Default: :any:`numpy.nan`
+            If :any:`None`, a random seed is used. If :any:`Ellipsis`,
+            the current seed will be kept. Default: :any:`Ellipsis`
         """
         # check if a new model is given
         if isinstance(model, CovModel):
             if self.model != model:
                 self._model = dcp(model)
-                if seed is None or not np.isnan(seed):
-                    self.reset_seed(seed)
-                else:
-                    self.reset_seed(self._seed)
+                self.reset_seed(self._seed if seed is Ellipsis else seed)
             # just update the seed, if its a new one
-            elif seed is None or not np.isnan(seed):
+            elif seed is not Ellipsis:
                 self.seed = seed
         # or just update the seed, when no model is given
-        elif model is None and (seed is None or not np.isnan(seed)):
+        elif model is None and seed is not Ellipsis:
             if isinstance(self._model, CovModel):
                 self.seed = seed
             else:
                 raise ValueError(
                     "gstools.field.generator.RandMeth: no 'model' given"
                 )
         # if the user tries to trick us, we beat him!
-        elif model is None and np.isnan(seed):
-            if not (
+        elif model is None and seed is Ellipsis:
+            if (
                 isinstance(self._model, CovModel)
                 and self._z_1 is not None
                 and self._z_2 is not None
@@ -287,22 +284,22 @@ def update(self, model=None, seed=np.nan):
                 "instance of 'gstools.CovModel'"
             )
 
-    def reset_seed(self, seed=np.nan):
+    def reset_seed(self, seed=...):
         """
         Recalculate the random amplitudes and wave numbers with the given seed.
 
         Parameters
         ----------
-        seed : :class:`int` or :any:`None` or :any:`numpy.nan`, optional
+        seed : :class:`int` or :any:`None` or :any:`Ellipsis`, optional
             the seed of the random number generator.
-            If :any:`None`, a random seed is used. If :any:`numpy.nan`,
-            the actual seed will be kept. Default: :any:`numpy.nan`
+            If :any:`None`, a random seed is used. If :any:`Ellipsis`,
+            the current seed will be kept. Default: :any:`Ellipsis`
 
         Notes
         -----
         Even if the given seed is the present one, modes will be recalculated.
         """
-        if seed is None or not np.isnan(seed):
+        if seed is not Ellipsis:
             self._seed = seed
         self._rng = RNG(self._seed)
         # normal distributed samples for randmeth
@@ -351,7 +348,7 @@ def seed(self):
 
     @seed.setter
     def seed(self, new_seed):
-        if new_seed is not self._seed:
+        if new_seed != self._seed:
             self.reset_seed(new_seed)
 
     @property

src/gstools/field/srf.py

@@ -103,7 +103,7 @@ def __init__(
     def __call__(
         self,
         pos=None,
-        seed=np.nan,
+        seed=...,
         point_volumes=0.0,
         mesh_type="unstructured",
         post_process=True,
@@ -118,8 +118,10 @@ def __call__(
         pos : :class:`list`, optional
             the position tuple, containing main direction and transversal
             directions
-        seed : :class:`int`, optional
-            seed for RNG for resetting. Default: keep seed from generator
+        seed : :class:`int` or :any:`None` or :any:`Ellipsis`, optional
+            the seed of the random number generator.
+            If :any:`None`, a random seed is used. If :any:`Ellipsis`,
+            the current seed will be kept. Default: :any:`Ellipsis`
         point_volumes : :class:`float` or :class:`numpy.ndarray`
             If your evaluation points for the field are coming from a mesh,
             they are probably representing a certain element volume.

src/gstools/krige/base.py

@@ -257,7 +257,7 @@ def __call__(
             ext_drift = self._pre_ext_drift(pnt_cnt, ext_drift)
             # iterate chunks
             for i in range(chunk_no):
-                # get chunk slice for actual chunk
+                # get chunk slice for current chunk
                 chunk_slice = (
                     i * chunk_size,
                     min(pnt_cnt, (i + 1) * chunk_size),