remove partial fix of defining np as an element. replace with more robust fix converting numpy array to scalars with .tolist() so element values appear without the type prefix in circtuit string (#322)

Author: BGerwe

impedance/models/circuits/elements.py

@@ -44,12 +44,6 @@ def wrapper(p, f):
             )
         else:
             circuit_elements[func.__name__] = wrapper
-        # Adding numpy to circuit_elements for proper evaluation with
-        # numpy>=2.0.0 because the scalar representation was changed.
-        # "Scalars are now printed as np.float64(3.0) rather than just 3.0."
-        # https://numpy.org/doc/2.0/release/2.0.0-notes.html
-        # #representation-of-numpy-scalars-changed
-        circuit_elements["np"] = np
 
         return wrapper
 

impedance/validation.py

@@ -265,14 +265,18 @@ def fit_linKK(f, ts, M, Z, fit_type='real', add_cap=False):
 
 def eval_linKK(elements, ts, f):
     """Builds a circuit of RC elements to be used in LinKK"""
-    circuit_string = f"s([R({[elements[0]]},{f.tolist()}),"
+    elements_list = elements.tolist()
+    ts_list = ts.tolist()
+    f_list = f.tolist()
 
-    for Rk, tk in zip(elements[1:], ts):
-        circuit_string += f"K({[Rk, tk]},{f.tolist()}),"
+    circuit_string = f"s([R({[elements_list[0]]},{f_list}),"
 
-    circuit_string += f"L({[elements[-1]]},{f.tolist()}),"
-    if elements.size == (ts.size + 3):
-        circuit_string += f"C({[1 / elements[-2]]},{f.tolist()}),"
+    for Rk, tk in zip(elements_list[1:], ts_list):
+        circuit_string += f"K({[Rk, tk]},{f_list}),"
+
+    circuit_string += f"L({[elements_list[-1]]},{f_list}),"
+    if len(elements_list) == (len(ts_list) + 3):
+        circuit_string += f"C({[1 / elements_list[-2]]},{f_list}),"
 
     circuit_string = circuit_string.strip(',')
     circuit_string += '])'