add sympy support; which can transfer your network into sympy expression;

add visualize in genome;
add related tests.

tensorneat/utils/__init__.py

@@ -1,6 +1,51 @@
-from .activation import Act, act_func, ACT_ALL
-from .aggregation import Agg, agg_func, AGG_ALL
+from utils.aggregation.agg_jnp import Agg, agg_func, AGG_ALL
 from .tools import *
 from .graph import *
 from .state import State
 from .stateful_class import StatefulBaseClass
+
+from .aggregation.agg_jnp import Agg, AGG_ALL, agg_func
+from .activation.act_jnp import Act, ACT_ALL, act_func
+from .aggregation.agg_sympy import *
+from .activation.act_sympy import *
+
+from typing import Union
+
+name2sympy = {
+    "sigmoid": SympySigmoid,
+    "tanh": SympyTanh,
+    "sin": SympySin,
+    "relu": SympyRelu,
+    "lelu": SympyLelu,
+    "identity": SympyIdentity,
+    "clamped": SympyClamped,
+    "inv": SympyInv,
+    "log": SympyLog,
+    "exp": SympyExp,
+    "abs": SympyAbs,
+    "sum": SympySum,
+    "product": SympyProduct,
+    "max": SympyMax,
+    "min": SympyMin,
+    "maxabs": SympyMaxabs,
+    "mean": SympyMean,
+}
+
+
+def convert_to_sympy(func: Union[str, callable]):
+    if isinstance(func, str):
+        name = func
+    else:
+        name = func.__name__
+    if name in name2sympy:
+        return name2sympy[name]
+    else:
+        raise ValueError(
+            f"Can not convert to sympy! Function {name} not found in name2sympy"
+        )
+
+
+FUNCS_MODULE = {}
+for cls in name2sympy.values():
+    if hasattr(cls, "numerical_eval"):
+        FUNCS_MODULE[cls.__name__] = cls.numerical_eval