MAINT: extend caching and review Surrogates API

pyproject.toml

@@ -47,7 +47,7 @@ jobs = 0
 disable = [
     "duplicate-code", "invalid-name", "fixme",
     "missing-docstring", "no-else-return",
-    "arguments-differ", "no-member", "no-name-in-module"
+    "arguments-differ", "no-name-in-module"
 ]
 
 [tool.pylint.format]

src/pyunicorn/timeseries/inter_system_recurrence_network.py

@@ -18,6 +18,9 @@
 analysis (RQA) and recurrence network analysis.
 """
 
+from typing import Tuple
+from collections.abc import Hashable
+
 # array object and fast numerics
 import numpy as np
 
@@ -211,22 +214,8 @@ def __str__(self):
     #  Service methods
     #
 
-    def clear_cache(self):
-        """
-        Clean up memory by deleting information that can be recalculated from
-        basic data.
-
-        Extends the clean up methods of the parent classes.
-        """
-        #  Call clean up of RecurrencePlot objects
-        self.rp_x.clear_cache()
-        self.rp_y.clear_cache()
-
-        #  Call clean up of CrossRecurrencePlot object
-        self.crp_xy.clear_cache()
-
-        #  Call clean up of InteractingNetworks
-        InteractingNetworks.clear_cache(self)
+    def __cache_state__(self) -> Tuple[Hashable, ...]:
+        return (self.rp_x, self.rp_x, self.crp_xy,)
 
     #
     #  Methods to handle inter system recurrence networks

src/pyunicorn/timeseries/joint_recurrence_network.py

@@ -158,18 +158,6 @@ def __str__(self):
                 f"{JointRecurrencePlot.__str__(self)}\n"
                 f"{Network.__str__(self)}")
 
-    def clear_cache(self):
-        """
-        Clean up memory by deleting information that can be recalculated from
-        basic data.
-
-        Extends the clean up methods of the parent classes.
-        """
-        #  Call clean up of RecurrencePlot
-        JointRecurrencePlot.clear_cache(self)
-        #  Call clean up of Network
-        Network.clear_cache(self)
-
     #
     #  Methods to handle recurrence networks
     #

src/pyunicorn/timeseries/recurrence_network.py

@@ -152,18 +152,6 @@ def __str__(self):
                 f"{RecurrencePlot.__str__(self)}\n"
                 f"{Network.__str__(self)}")
 
-    def clear_cache(self):
-        """
-        Clean up memory by deleting information that can be recalculated from
-        basic data.
-
-        Extends the clean up methods of the parent classes.
-        """
-        #  Call clean up of RecurrencePlot
-        RecurrencePlot.clear_cache(self)
-        #  Call clean up of Network
-        Network.clear_cache(self)
-
     #
     #  Methods to handle recurrence networks
     #