Created equivalent_resistance under Electronics

electronics/resistor_equivalence.py

@@ -0,0 +1,57 @@
+# https://byjus.com/equivalent-resistance-formula/
+
+from __future__ import annotations
+
+
+def resistor_parallel(
+    resistors: list[float],
+) -> float:  # Req = 1/ (1/R1 + 1/R2 + ... + 1/Rn)
+    """
+    >>> resistor_parallel([3.21389, 2, 3])
+    0.8737571620498019
+    >>> resistor_parallel([3.21389, 2, -3])
+    Traceback (most recent call last):
+        ...
+    ValueError: Resistor at index 2 has a negative or zero value!
+    >>> resistor_parallel([3.21389, 2, 0.000])
+    Traceback (most recent call last):
+        ...
+    ValueError: Resistor at index 2 has a negative or zero value!
+    """
+
+    firstSum = 0.00
+    index = 0
+    for resistor in resistors:
+        if resistor <= 0:
+            raise ValueError(f"Resistor at index {index} has a negative or zero value!")
+        firstSum += 1 / float(resistor)
+        index += 1
+    return 1 / firstSum
+
+
+def resistor_series(resistors: list[float]) -> float:  # Req = R1 + R2 + ... + Rn
+    """
+    This function can calculate the equivalent resistance for any number of
+    resistors in parallel.
+    >>> resistor_series([3.21389, 2, 3])
+    8.21389
+    >>> resistor_series([3.21389, 2, -3])
+    Traceback (most recent call last):
+        ...
+    ValueError: Resistor at index 2 has a negative value!
+    """
+    sum = 0.00
+    index = 0
+    for resistor in resistors:
+
+        sum += resistor
+        if resistor < 0:
+            raise ValueError(f"Resistor at index {index} has a negative value!")
+        index += 1
+    return sum
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()