Ohm's Law algorithm added

electronics/ohms_law.py

@@ -0,0 +1,39 @@
+# https://en.wikipedia.org/wiki/Ohm%27s_law
+
+
+def ohms_law(voltage: float, current: float, resistance: float) -> float:
+    """
+    Apply Ohm's Law, on any two given electrical values, which can be voltage, current,
+    and resistance, and then in a Python dict return name/value pair of the zero value.
+
+    >>> ohms_law(voltage=10, resistance=5, current=0)
+    {'current': 2.0}
+    >>> ohms_law(voltage=0, current=0, resistance=10)
+    Traceback (most recent call last):
+      ...
+    ValueError: One and only one argument must be 0
+    >>> ohms_law(voltage=0, current=1, resistance=-2)
+    Traceback (most recent call last):
+      ...
+    ValueError: Resistance cannot be negative
+    >>> ohms_law(resistance=0, voltage=-10, current=1)
+    {'resistance': -10.0}
+    >>> ohms_law(voltage=0, current=-1.5, resistance=2)
+    {'voltage': -3.0}
+    """
+    if (voltage, current, resistance).count(0) != 1:
+        raise ValueError("One and only one argument must be 0")
+    if resistance < 0:
+        raise ValueError("Resistance cannot be negative")
+    if voltage == 0:
+        return {"voltage": float(current * resistance)}
+    elif current == 0:
+        return {"current": voltage / resistance}
+    elif resistance == 0:
+        return {"resistance": voltage / current}
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()