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        "\n\n# Basic units\n\n\nThis file implements a units library that supports registering arbitrary units,\nconversions between units, and math with unitized data. This library also implements a\nMatplotlib unit converter and registers its units with Matplotlib. This library is used\nin the examples to demonstrate Matplotlib's unit support. It is only maintained for the\npurposes of building documentation and should never be used outside of the Matplotlib\ndocumentation.\n"
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        "import itertools\nimport math\n\nfrom packaging.version import parse as parse_version\n\nimport numpy as np\n\nimport matplotlib.ticker as ticker\nimport matplotlib.units as units\n\n\nclass ProxyDelegate:\n    def __init__(self, fn_name, proxy_type):\n        self.proxy_type = proxy_type\n        self.fn_name = fn_name\n\n    def __get__(self, obj, objtype=None):\n        return self.proxy_type(self.fn_name, obj)\n\n\nclass TaggedValueMeta(type):\n    def __init__(self, name, bases, dict):\n        for fn_name in self._proxies:\n            if not hasattr(self, fn_name):\n                setattr(self, fn_name,\n                        ProxyDelegate(fn_name, self._proxies[fn_name]))\n\n\nclass PassThroughProxy:\n    def __init__(self, fn_name, obj):\n        self.fn_name = fn_name\n        self.target = obj.proxy_target\n\n    def __call__(self, *args):\n        fn = getattr(self.target, self.fn_name)\n        ret = fn(*args)\n        return ret\n\n\nclass ConvertArgsProxy(PassThroughProxy):\n    def __init__(self, fn_name, obj):\n        super().__init__(fn_name, obj)\n        self.unit = obj.unit\n\n    def __call__(self, *args):\n        converted_args = []\n        for a in args:\n            try:\n                converted_args.append(a.convert_to(self.unit))\n            except AttributeError:\n                converted_args.append(TaggedValue(a, self.unit))\n        converted_args = tuple([c.get_value() for c in converted_args])\n        return super().__call__(*converted_args)\n\n\nclass ConvertReturnProxy(PassThroughProxy):\n    def __init__(self, fn_name, obj):\n        super().__init__(fn_name, obj)\n        self.unit = obj.unit\n\n    def __call__(self, *args):\n        ret = super().__call__(*args)\n        return (NotImplemented if ret is NotImplemented\n                else TaggedValue(ret, self.unit))\n\n\nclass ConvertAllProxy(PassThroughProxy):\n    def __init__(self, fn_name, obj):\n        super().__init__(fn_name, obj)\n        self.unit = obj.unit\n\n    def __call__(self, *args):\n        converted_args = []\n        arg_units = [self.unit]\n        for a in args:\n            if hasattr(a, 'get_unit') and not hasattr(a, 'convert_to'):\n                # If this argument has a unit type but no conversion ability,\n                # this operation is prohibited.\n                return NotImplemented\n\n            if hasattr(a, 'convert_to'):\n                try:\n                    a = a.convert_to(self.unit)\n                except Exception:\n                    pass\n                arg_units.append(a.get_unit())\n                converted_args.append(a.get_value())\n            else:\n                converted_args.append(a)\n                if hasattr(a, 'get_unit'):\n                    arg_units.append(a.get_unit())\n                else:\n                    arg_units.append(None)\n        converted_args = tuple(converted_args)\n        ret = super().__call__(*converted_args)\n        if ret is NotImplemented:\n            return NotImplemented\n        ret_unit = unit_resolver(self.fn_name, arg_units)\n        if ret_unit is NotImplemented:\n            return NotImplemented\n        return TaggedValue(ret, ret_unit)\n\n\nclass TaggedValue(metaclass=TaggedValueMeta):\n\n    _proxies = {'__add__': ConvertAllProxy,\n                '__sub__': ConvertAllProxy,\n                '__mul__': ConvertAllProxy,\n                '__rmul__': ConvertAllProxy,\n                '__cmp__': ConvertAllProxy,\n                '__lt__': ConvertAllProxy,\n                '__gt__': ConvertAllProxy,\n                '__len__': PassThroughProxy}\n\n    def __new__(cls, value, unit):\n        # generate a new subclass for value\n        value_class = type(value)\n        try:\n            subcls = type(f'TaggedValue_of_{value_class.__name__}',\n                          (cls, value_class), {})\n            return object.__new__(subcls)\n        except TypeError:\n            return object.__new__(cls)\n\n    def __init__(self, value, unit):\n        self.value = value\n        self.unit = unit\n        self.proxy_target = self.value\n\n    def __copy__(self):\n        return TaggedValue(self.value, self.unit)\n\n    def __getattribute__(self, name):\n        if name.startswith('__'):\n            return object.__getattribute__(self, name)\n        variable = object.__getattribute__(self, 'value')\n        if hasattr(variable, name) and name not in self.__class__.__dict__:\n            return getattr(variable, name)\n        return object.__getattribute__(self, name)\n\n    def __array__(self, dtype=object, copy=False):\n        return np.asarray(self.value, dtype)\n\n    def __array_wrap__(self, array, context=None, return_scalar=False):\n        return TaggedValue(array, self.unit)\n\n    def __repr__(self):\n        return f'TaggedValue({self.value!r}, {self.unit!r})'\n\n    def __str__(self):\n        return f\"{self.value} in {self.unit}\"\n\n    def __len__(self):\n        return len(self.value)\n\n    if parse_version(np.__version__) >= parse_version('1.20'):\n        def __getitem__(self, key):\n            return TaggedValue(self.value[key], self.unit)\n\n    def __iter__(self):\n        # Return a generator expression rather than use `yield`, so that\n        # TypeError is raised by iter(self) if appropriate when checking for\n        # iterability.\n        return (TaggedValue(inner, self.unit) for inner in self.value)\n\n    def get_compressed_copy(self, mask):\n        new_value = np.ma.masked_array(self.value, mask=mask).compressed()\n        return TaggedValue(new_value, self.unit)\n\n    def convert_to(self, unit):\n        if unit == self.unit or not unit:\n            return self\n        try:\n            new_value = self.unit.convert_value_to(self.value, unit)\n        except AttributeError:\n            new_value = self\n        return TaggedValue(new_value, unit)\n\n    def get_value(self):\n        return self.value\n\n    def get_unit(self):\n        return self.unit\n\n\nclass BasicUnit:\n    # numpy scalars convert eager and np.float64(2) * BasicUnit('cm')\n    # would thus return a numpy scalar. To avoid this, we increase the\n    # priority of the BasicUnit.\n    __array_priority__ = np.float64(0).__array_priority__ + 1\n\n    def __init__(self, name, fullname=None):\n        self.name = name\n        if fullname is None:\n            fullname = name\n        self.fullname = fullname\n        self.conversions = dict()\n\n    def __repr__(self):\n        return f'BasicUnit({self.name})'\n\n    def __str__(self):\n        return self.fullname\n\n    def __call__(self, value):\n        return TaggedValue(value, self)\n\n    def __mul__(self, rhs):\n        value = rhs\n        unit = self\n        if hasattr(rhs, 'get_unit'):\n            value = rhs.get_value()\n            unit = rhs.get_unit()\n            unit = unit_resolver('__mul__', (self, unit))\n        if unit is NotImplemented:\n            return NotImplemented\n        return TaggedValue(value, unit)\n\n    def __rmul__(self, lhs):\n        return self*lhs\n\n    def __array_wrap__(self, array, context=None, return_scalar=False):\n        return TaggedValue(array, self)\n\n    def __array__(self, t=None, context=None, copy=False):\n        ret = np.array(1)\n        if t is not None:\n            return ret.astype(t)\n        else:\n            return ret\n\n    def add_conversion_factor(self, unit, factor):\n        def convert(x):\n            return x*factor\n        self.conversions[unit] = convert\n\n    def add_conversion_fn(self, unit, fn):\n        self.conversions[unit] = fn\n\n    def get_conversion_fn(self, unit):\n        return self.conversions[unit]\n\n    def convert_value_to(self, value, unit):\n        conversion_fn = self.conversions[unit]\n        ret = conversion_fn(value)\n        return ret\n\n    def get_unit(self):\n        return self\n\n\nclass UnitResolver:\n    def addition_rule(self, units):\n        for unit_1, unit_2 in itertools.pairwise(units):\n            if unit_1 != unit_2:\n                return NotImplemented\n        return units[0]\n\n    def multiplication_rule(self, units):\n        non_null = [u for u in units if u]\n        if len(non_null) > 1:\n            return NotImplemented\n        return non_null[0]\n\n    op_dict = {\n        '__mul__': multiplication_rule,\n        '__rmul__': multiplication_rule,\n        '__add__': addition_rule,\n        '__radd__': addition_rule,\n        '__sub__': addition_rule,\n        '__rsub__': addition_rule}\n\n    def __call__(self, operation, units):\n        if operation not in self.op_dict:\n            return NotImplemented\n\n        return self.op_dict[operation](self, units)\n\n\nunit_resolver = UnitResolver()\n\ncm = BasicUnit('cm', 'centimeters')\ninch = BasicUnit('inch', 'inches')\ninch.add_conversion_factor(cm, 2.54)\ncm.add_conversion_factor(inch, 1/2.54)\n\nradians = BasicUnit('rad', 'radians')\ndegrees = BasicUnit('deg', 'degrees')\nradians.add_conversion_factor(degrees, 180.0/np.pi)\ndegrees.add_conversion_factor(radians, np.pi/180.0)\n\nsecs = BasicUnit('s', 'seconds')\nhertz = BasicUnit('Hz', 'Hertz')\nminutes = BasicUnit('min', 'minutes')\n\nsecs.add_conversion_fn(hertz, lambda x: 1./x)\nsecs.add_conversion_factor(minutes, 1/60.0)\n\n\n# radians formatting\ndef rad_fn(x, pos=None):\n    if x >= 0:\n        n = int((x / np.pi) * 2.0 + 0.25)\n    else:\n        n = int((x / np.pi) * 2.0 - 0.25)\n\n    if n == 0:\n        return '0'\n    elif n == 1:\n        return r'$\\pi/2$'\n    elif n == 2:\n        return r'$\\pi$'\n    elif n == -1:\n        return r'$-\\pi/2$'\n    elif n == -2:\n        return r'$-\\pi$'\n    elif n % 2 == 0:\n        return fr'${n//2}\\pi$'\n    else:\n        return fr'${n}\\pi/2$'\n\n\nclass BasicUnitConverter(units.ConversionInterface):\n    @staticmethod\n    def axisinfo(unit, axis):\n        \"\"\"Return AxisInfo instance for x and unit.\"\"\"\n\n        if unit == radians:\n            return units.AxisInfo(\n                majloc=ticker.MultipleLocator(base=np.pi/2),\n                majfmt=ticker.FuncFormatter(rad_fn),\n                label=unit.fullname,\n            )\n        elif unit == degrees:\n            return units.AxisInfo(\n                majloc=ticker.AutoLocator(),\n                majfmt=ticker.FormatStrFormatter(r'$%i^\\circ$'),\n                label=unit.fullname,\n            )\n        elif unit is not None:\n            if hasattr(unit, 'fullname'):\n                return units.AxisInfo(label=unit.fullname)\n            elif hasattr(unit, 'unit'):\n                return units.AxisInfo(label=unit.unit.fullname)\n        return None\n\n    @staticmethod\n    def convert(val, unit, axis):\n        if np.iterable(val):\n            if isinstance(val, np.ma.MaskedArray):\n                val = val.astype(float).filled(np.nan)\n            out = np.empty(len(val))\n            for i, thisval in enumerate(val):\n                if np.ma.is_masked(thisval):\n                    out[i] = np.nan\n                else:\n                    try:\n                        out[i] = thisval.convert_to(unit).get_value()\n                    except AttributeError:\n                        out[i] = thisval\n            return out\n        if np.ma.is_masked(val):\n            return np.nan\n        else:\n            return val.convert_to(unit).get_value()\n\n    @staticmethod\n    def default_units(x, axis):\n        \"\"\"Return the default unit for x or None.\"\"\"\n        if np.iterable(x):\n            for thisx in x:\n                return thisx.unit\n        return x.unit\n\n\ndef cos(x):\n    if np.iterable(x):\n        return [math.cos(val.convert_to(radians).get_value()) for val in x]\n    else:\n        return math.cos(x.convert_to(radians).get_value())\n\n\nunits.registry[BasicUnit] = units.registry[TaggedValue] = BasicUnitConverter()"
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