utils + parallel resistors calculator

voltage_divider.py

@@ -1,5 +1,5 @@
 #!/bin/python
-import re
+from utils import parse_resistors
 
 def find_bests(desired_ratio, resistors):
     # only keep the 5 best candidates
@@ -22,31 +22,6 @@ def find_bests(desired_ratio, resistors):
     for i, (error, R1, R2, ratio) in enumerate(candidates, start=1):
         print(f"{i}. R1 = {R1} Ω, R2 = {R2} Ω  -> ratio = {ratio:.6f}, error = {error:.6e}")
 
-def parse_resistors(raw_input):
-    values = []
-    tokens = raw_input.replace(',', ' ').split()
-
-    for token in tokens:
-        match = re.fullmatch(r'([0-9]*\.?[0-9]+)\s*([KM]?)', token)
-        if not match:
-            raise ValueError(f"Invalid component value '{token}'")
-
-        number = float(match.group(1))
-        if number <= 0:
-            raise ValueError(f"Invalid component value '{token}' (must be positive)")
-
-        suffix = match.group(2)
-        if suffix == 'K':
-            multiplier = 1e3
-        elif suffix == 'M':
-            multiplier = 1e6
-        else:
-            multiplier = 1.0
-
-        values.append(number * multiplier)
-
-    return values
-
 def get_ratio():
     while True:
         try: