added units

units.py

@@ -0,0 +1,109 @@
+from enum import Enum, auto
+from math import pi
+
+
+class UnitClass(Enum):
+    NONE = auto()
+    LENGTH = auto()
+    SPEED = auto()
+    TIME = auto()
+    ANGLE = auto()
+
+
+class Unit(Enum):
+    KM_H = auto(), UnitClass.SPEED
+    M_S = auto(), UnitClass.SPEED
+    KM = auto(), UnitClass.LENGTH
+    M = auto(), UnitClass.LENGTH
+    SEC = auto(), UnitClass.TIME
+    MIN = auto(), UnitClass.TIME
+    HOUR = auto(), UnitClass.TIME
+    DEG = auto(), UnitClass.ANGLE
+    RAD = auto(), UnitClass.ANGLE
+    NONE = auto(), UnitClass.NONE
+
+    def __init__(self, v: int, cls: UnitClass):
+        self.cls: UnitClass = cls
+
+
+class Value:
+    def __init__(self, value: float, unit: Unit):
+        self.value: float = value
+        self.unit: Unit = unit
+
+    def convert(self, to_unit: Unit) -> "Value":
+        if self.unit == to_unit:
+            return self
+
+        from_cls = self.unit.cls
+        to_cls = to_unit.cls
+
+        if from_cls != to_cls:
+            raise ValueError(f"Cannot convert from {from_cls} to {to_cls}")
+
+        cls = from_cls
+
+        if cls == UnitClass.NONE:
+            to_value = self.value
+
+        elif cls == UnitClass.LENGTH:
+            value = self.value
+            if self.unit == Unit.KM:
+                value *= 1000
+
+            to_value = value
+
+            if to_unit == Unit.KM:
+                to_value /= 1000
+
+        elif cls == UnitClass.TIME:
+            value = self.value
+            if self.unit == Unit.MIN:
+                value *= 60
+            elif self.unit == Unit.HOUR:
+                value *= 3600
+
+            to_value = value
+
+            if to_unit == Unit.MIN:
+                to_value /= 60
+            elif self.unit == Unit.HOUR:
+                to_value /= 3600
+
+        elif cls == UnitClass.SPEED:
+            value = self.value
+            if self.unit == Unit.KM_H:
+                value /= 3.6
+
+            to_value = value
+
+            if to_unit == Unit.KM_H:
+                to_value *= 3.6
+
+        elif cls == UnitClass.ANGLE:
+            value = self.value
+            if self.unit == Unit.RAD:
+                value *= 180 / pi
+
+            to_value = value
+
+            if to_unit == Unit.RAD:
+                value *= pi / 180
+
+        else:
+            raise ValueError(f"Unknown unit class: {cls}")
+
+        return Value(to_value, to_unit)
+
+    def __repr__(self):
+        return f"{self.value} [{self.unit}]"
+
+
+if __name__ == '__main__':
+    v1 = Value(765, Unit.KM_H)
+    print(v1)
+    print(v1.convert(Unit.M_S))
+
+    v2 = Value(120, Unit.SEC)
+    print(v2)
+    print(v2.convert(Unit.MIN))