Merge pull request #190 from SasView/172_unrecognized_units

172 unrecognized units (Again)

Author: krzywon

sasdata/quantities/_units_base.py

@@ -1,10 +1,9 @@
-from collections.abc import Sequence
-from dataclasses import dataclass
+import re
 from fractions import Fraction
 from typing import Self
 
 import numpy as np
-from unicode_superscript import int_as_unicode_superscript
+from unicode_superscript import int_as_unicode_superscript  # type: ignore[import-untyped]
 
 
 class DimensionError(Exception):
@@ -111,15 +110,15 @@ def __pow__(self, power: int | float):
             (self.moles_hint * numerator) // denominator,
             (self.angle_hint * numerator) // denominator)
 
-    def __eq__(self: Self, other: Self):
+    def __eq__(self: Self, other: object) -> bool:
         if isinstance(other, Dimensions):
-            return (self.length == other.length and
-                    self.time == other.time and
-                    self.mass == other.mass and
-                    self.current == other.current and
-                    self.temperature == other.temperature and
-                    self.moles_hint == other.moles_hint and
-                    self.angle_hint == other.angle_hint)
+            return (self.length == other.length
+                    and self.time == other.time
+                    and self.mass == other.mass
+                    and self.current == other.current
+                    and self.temperature == other.temperature
+                    and self.moles_hint == other.moles_hint
+                    and self.angle_hint == other.angle_hint)
 
         return NotImplemented
 
@@ -210,9 +209,6 @@ def __init__(self,
         self.scale = si_scaling_factor
         self.dimensions = dimensions
 
-    def _components(self, tokens: Sequence["UnitToken"]):
-        pass
-
     def __mul__(self: Self, other: "Unit"):
         if isinstance(other, Unit):
             return Unit(self.scale * other.scale, self.dimensions * other.dimensions)
@@ -246,17 +242,15 @@ def __pow__(self, power: int | float):
     def equivalent(self: Self, other: "Unit"):
         return self.dimensions == other.dimensions
 
-    def __eq__(self: Self, other: "Unit"):
-        return self.equivalent(other) and np.abs(np.log(self.scale/other.scale)) < 1e-5
+    def __eq__(self: Self, other: object) -> bool:
+        if isinstance(other, Unit):
+            return self.equivalent(other) and np.abs(np.log(self.scale/other.scale)) < 1e-5
+        return False
 
     def si_equivalent(self):
         """ Get the SI unit corresponding to this unit"""
         return Unit(1, self.dimensions)
 
-    def _format_unit(self, format_process: list["UnitFormatProcessor"]):
-        for processor in format_process:
-            pass
-
     def __repr__(self):
         if self.scale == 1:
             # We're in SI
@@ -265,9 +259,6 @@ def __repr__(self):
         else:
             return f"Unit[{self.scale}, {self.dimensions}]"
 
-    @staticmethod
-    def parse(unit_string: str) -> "Unit":
-        pass
 
 class NamedUnit(Unit):
     """ Units, but they have a name, and a symbol
@@ -308,57 +299,204 @@ def __eq__(self, other):
             case _:
                 return False
 
-
     def startswith(self, prefix: str) -> bool:
         """Check if any representation of the unit begins with the prefix string"""
         prefix = prefix.lower()
         return (self.name is not None and self.name.lower().startswith(prefix)) \
-                or (self.ascii_symbol is not None and self.ascii_symbol.lower().startswith(prefix)) \
-                or (self.symbol is not None and self.symbol.lower().startswith(prefix))
-
-#
-# Parsing plan:
-#  Require unknown amounts of units to be explicitly positive or negative?
-#
-#
-
-
-
-@dataclass
-class ProcessedUnitToken:
-    """ Mid processing representation of formatted units """
-    base_string: str
-    exponent_string: str
-    latex_exponent_string: str
-    exponent: int
-
-class UnitFormatProcessor:
-    """ Represents a step in the unit processing pipeline"""
-    def apply(self, scale, dimensions) -> tuple[ProcessedUnitToken, float, Dimensions]:
-        """ This will be called to deal with each processing stage"""
-
-class RequiredUnitFormatProcessor(UnitFormatProcessor):
-    """ This unit is required to exist in the formatting """
-    def __init__(self, unit: Unit, power: int = 1):
-        self.unit = unit
-        self.power = power
-    def apply(self, scale, dimensions) -> tuple[float, Dimensions, ProcessedUnitToken]:
-        new_scale = scale / (self.unit.scale * self.power)
-        new_dimensions = self.unit.dimensions / (dimensions**self.power)
-        token = ProcessedUnitToken(self.unit, self.power)
-
-        return new_scale, new_dimensions, token
-class GreedyAbsDimensionUnitFormatProcessor(UnitFormatProcessor):
-    """ This processor minimises the dimensionality of the unit by multiplying by as many
-    units of the specified type as needed """
-    def __init__(self, unit: Unit):
-        self.unit = unit
-
-    def apply(self, scale, dimensions) -> tuple[ProcessedUnitToken, float, Dimensions]:
-        pass
-
-class GreedyAbsDimensionUnitFormatProcessor(UnitFormatProcessor):
-    pass
+            or (self.ascii_symbol is not None and self.ascii_symbol.lower().startswith(prefix)) \
+            or (self.symbol is not None and self.symbol.lower().startswith(prefix))
+
+
+class UnknownUnit(NamedUnit):
+    """A unit for an unknown quantity
+
+    While this library attempts to handle all known SI units, it is
+    likely that users will want to express quantities of arbitrary
+    units (for example, calculating donuts per person for a meeting).
+    The arbitrary unit allows for these unforseeable quantities."""
+
+    def __init__(self,
+                 numerator: str | list[str] | dict[str, int | float],
+                 denominator: None | list[str] | dict[str, int | float] = None):
+        if numerator is None:
+            return TypeError
+        self._numerator = UnknownUnit._parse_arg(numerator)
+        self._denominator = UnknownUnit._parse_arg(denominator)
+        self._unit = NamedUnit(1, Dimensions(), "")  # Unitless
+
+        super().__init__(si_scaling_factor=1, dimensions=self._unit.dimensions, symbol=self._name())
+
+    @staticmethod
+    def _parse_arg(arg: str | list[str] | dict[str, int | float] | None) -> dict[str, int | float]:
+        """Parse the different possibilities for constructor arguments
+
+        Both the numerator and the denominator could be a string, a
+        list of strings, or a dict.  Parse any of these values into a
+        dictionary of names and powers.
+
+        """
+        match arg:
+            case None:
+                return {}
+            case str():
+                return {UnknownUnit._valid_name(arg): 1}
+            case list():
+                result: dict[str, int | float] = {}
+                for key in arg:
+                    if key in result:
+                        result[key] += 1
+                    else:
+                        UnknownUnit._valid_name(key)
+                        result[key] = 1
+                return result
+            case dict():
+                for key in arg:
+                    UnknownUnit._valid_name(key)
+                return arg
+            case _:
+                raise TypeError
+
+    @staticmethod
+    def _valid_name(name: str) -> str:
+        """Confirms that the name of a unit is appropriate
+
+        This mostly confirms that the unit does not contain math
+        operators that would act on other units, like / or ^
+        """
+
+        if re.search(r"[*/^\s]", name):
+            raise RuntimeError(f'Unit name "{name}" contains invalid characters (*, /, ^, or whitespace)')
+
+        return name
+
+    def _name(self):
+        num = []
+        for key, value in self._numerator.items():
+            if value == 1:
+                num.append(key)
+            else:
+                num.append(f"{key}^{value}")
+        den = []
+        for key, value in self._denominator.items():
+            den.append(f"{key}^{-value}")
+        num.sort()
+        den.sort()
+        return " ".join(num + den)
+
+    def __eq__(self, other):
+        match other:
+            case UnknownUnit():
+                return self._numerator == other._numerator and self._denominator == other._denominator and self._unit == other._unit
+            case Unit():
+                return not self._numerator and not self._denominator and self._unit == other
+            case _:
+                return False
+
+    def __mul__(self: Self, other: "Unit"):
+        match other:
+            case UnknownUnit():
+                num = dict(self._numerator)
+                for key in other._numerator:
+                    if key in num:
+                        num[key] += other._numerator[key]
+                    else:
+                        num[key] = other._numerator[key]
+                den = dict(self._denominator)
+                for key in other._denominator:
+                    if key in den:
+                        den[key] += other._denominator[key]
+                    else:
+                        den[key] = other._denominator[key]
+                result = UnknownUnit(num, den)
+                result._unit *= other._unit
+                return result._reduce()
+            case NamedUnit() | Unit() | int() | float():
+                result = UnknownUnit(self._numerator, self._denominator)
+                result._unit *= other
+                return result
+            case _:
+                return NotImplemented
+
+    def __rmul__(self: Self, other):
+        return self * other
+
+    def __truediv__(self: Self, other: "Unit") -> "UnknownUnit":
+        match other:
+            case UnknownUnit():
+                num = dict(self._numerator)
+                for key in other._denominator:
+                    if key in num:
+                        num[key] += other._denominator[key]
+                    else:
+                        num[key] = other._denominator[key]
+                den = dict(self._denominator)
+                for key in other._numerator:
+                    if key in den:
+                        den[key] += other._numerator[key]
+                    else:
+                        den[key] = other._numerator[key]
+                result = UnknownUnit(num, den)
+                result._unit /= other._unit
+                return result._reduce()
+            case NamedUnit() | Unit() | int() | float():
+                result = UnknownUnit(self._numerator, self._denominator)
+                result._unit /= other
+                return result
+            case _:
+                return NotImplemented
+
+    def __rtruediv__(self: Self, other: "Unit") -> "UnknownUnit":
+        return (self/other) ** -1
+
+    def __pow__(self, power: int | float) -> "UnknownUnit":
+        match power:
+            case int() | float():
+                num = {key: value * power for key, value in self._numerator.items()}
+                den = {key: value * power for key, value in self._denominator.items()}
+                if power < 0:
+                    num, den = den, num
+                    num = {k: -v for k,v in num.items()}
+                    den = {k: -v for k,v in den.items()}
+
+                result = UnknownUnit(num, den)
+                result._unit = self._unit ** power
+                return result
+            case _:
+                return NotImplemented
+
+    def equivalent(self: Self, other: "Unit"):
+        match other:
+            case UnknownUnit():
+                return self._unit.equivalent(other._unit) and sorted(self._numerator) == sorted(other._numerator) and sorted(self._denominator) == sorted(other._denominator)
+            case _:
+                return False
+
+    def _reduce(self):
+        """Remove redundant units"""
+        for k in self._denominator:
+            if k in self._numerator:
+                common = min(self._numerator[k], self._denominator[k])
+                self._numerator[k] -= common
+                self._denominator[k] -= common
+        dead_nums = [k for k in self._numerator if self._numerator[k] == 0]
+        for k in dead_nums:
+            del self._numerator[k]
+        dead_dens = [k for k in self._denominator if self._denominator[k] == 0]
+        for k in dead_dens:
+            del self._denominator[k]
+        return self
+
+    def __str__(self):
+        result = self._name()
+        if type(self._unit) is NamedUnit and self._unit.name.strip():
+            result += f" {self._unit.name.strip()}"
+        if type(self._unit) is Unit and str(self._unit).strip():
+            result += f" {str(self._unit).strip()}"
+        return result
+
+    def __repr__(self):
+        return str(self)
+
 
 class UnitGroup:
     """ A group of units that all have the same dimensionality """

sasdata/quantities/accessors.py

@@ -9479,6 +9479,14 @@ def radians(self) -> T:
         else:
             return quantity.in_units_of(units.radians)
 
+    @property
+    def rotations(self) -> T:
+        quantity = self.quantity
+        if quantity is None:
+            return None
+        else:
+            return quantity.in_units_of(units.rotations)
+
 
 
 class SolidangleAccessor[T](QuantityAccessor[T]):