DEP: Deprecate finfo.machar

Author: BvB93

doc/release/upcoming_changes/20201.deprecation.rst

@@ -1,5 +1,5 @@
 The ``np.MachAr`` class has been deprecated
 -------------------------------------------
-The `~numpy.MachAr` class has been deprecated. Users are encouraged to
-use either `np.finfo(...).machar <numpy.finfo>`, or, if applicable, directly
-access the attribute of interest from the finfo instance.
+The `~numpy.MachAr` class and `finfo.machar <numpy.finfo>` attribute have
+been deprecated. Users are encouraged to access the property if interest
+directly from the corresponding `~numpy.finfo` attribute.

numpy/__init__.pyi

@@ -14,7 +14,6 @@ if sys.version_info >= (3, 9):
 
 from numpy._pytesttester import PytestTester
 from numpy.core._internal import _ctypes
-from numpy.core.getlimits import MachArLike
 
 from numpy.typing import (
     # Arrays
@@ -3384,14 +3383,6 @@ class finfo(Generic[_FloatType]):
     def smallest_normal(self) -> _FloatType: ...
     @property
     def tiny(self) -> _FloatType: ...
-
-    # NOTE: Not technically a property, but this is the only way we can
-    # access the precision of the underlying float
-    @property
-    def machar(self: finfo[floating[_NBit1]]) -> MachArLike[_NBit1]: ...
-    @machar.setter
-    def machar(self: finfo[floating[_NBit1]], value: MachArLike[_NBit1]) -> None: ...
-
     @overload
     def __new__(
         cls, dtype: inexact[_NBit1] | _DTypeLike[inexact[_NBit1]]

numpy/core/getlimits.py

@@ -385,6 +385,8 @@ class finfo:
     machar : MachAr
         The object which calculated these parameters and holds more
         detailed information.
+
+        .. deprecated:: 1.22
     machep : int
         The exponent that yields `eps`.
     max : floating point number of the appropriate type
@@ -501,7 +503,7 @@ def _init(self, dtype):
         self.eps = machar.eps.flat[0]
         self.nexp = machar.iexp
         self.nmant = machar.it
-        self.machar = machar
+        self._machar = machar
         self._str_tiny = machar._str_xmin.strip()
         self._str_max = machar._str_xmax.strip()
         self._str_epsneg = machar._str_epsneg.strip()
@@ -551,11 +553,11 @@ def smallest_normal(self):
         """
         # This check is necessary because the value for smallest_normal is
         # platform dependent for longdouble types.
-        if isnan(self.machar.smallest_normal.flat[0]):
+        if isnan(self._machar.smallest_normal.flat[0]):
             warnings.warn(
                 'The value of smallest normal is undefined for double double',
                 UserWarning, stacklevel=2)
-        return self.machar.smallest_normal.flat[0]
+        return self._machar.smallest_normal.flat[0]
 
     @property
     def tiny(self):
@@ -574,6 +576,20 @@ def tiny(self):
         """
         return self.smallest_normal
 
+    @property
+    def machar(self):
+        """The object which calculated these parameters and holds more
+        detailed information.
+
+        .. deprecated:: 1.22
+        """
+        # Deprecated 2021-10-27, NumPy 1.22
+        warnings.warn(
+            "`finfo.machar` is deprecated (NumPy 1.22)",
+            DeprecationWarning, stacklevel=2,
+        )
+        return self._machar
+
 
 @set_module('numpy')
 class iinfo:

numpy/core/getlimits.pyi

@@ -1,58 +1,8 @@
-from typing import Any, Generic, List, Type, TypeVar
+from typing import List
 
 from numpy import (
     finfo as finfo,
     iinfo as iinfo,
-    floating,
-    signedinteger,
 )
 
-from numpy.typing import NBitBase, NDArray
-
-_NBit = TypeVar("_NBit", bound=NBitBase)
-
 __all__: List[str]
-
-class MachArLike(Generic[_NBit]):
-    def __init__(
-        self,
-        ftype: Type[floating[_NBit]],
-        *,
-        eps: floating[Any],
-        epsneg: floating[Any],
-        huge: floating[Any],
-        tiny: floating[Any],
-        ibeta: int,
-        smallest_subnormal: None | floating[Any] = ...,
-        # Expand `**kwargs` into keyword-only arguments
-        machep: int,
-        negep: int,
-        minexp: int,
-        maxexp: int,
-        it: int,
-        iexp: int,
-        irnd: int,
-        ngrd: int,
-    ) -> None: ...
-    @property
-    def smallest_subnormal(self) -> NDArray[floating[_NBit]]: ...
-    eps: NDArray[floating[_NBit]]
-    epsilon: NDArray[floating[_NBit]]
-    epsneg: NDArray[floating[_NBit]]
-    huge: NDArray[floating[_NBit]]
-    ibeta: signedinteger[_NBit]
-    iexp: int
-    irnd: int
-    it: int
-    machep: int
-    maxexp: int
-    minexp: int
-    negep: int
-    ngrd: int
-    precision: int
-    resolution: NDArray[floating[_NBit]]
-    smallest_normal: NDArray[floating[_NBit]]
-    tiny: NDArray[floating[_NBit]]
-    title: str
-    xmax: NDArray[floating[_NBit]]
-    xmin: NDArray[floating[_NBit]]

numpy/core/tests/test_deprecations.py

@@ -1226,3 +1226,7 @@ def test_deprecated(self):
 
     def test_deprecated_module(self):
         self.assert_deprecated(lambda: getattr(np.core, "machar"))
+
+    def test_deprecated_attr(self):
+        finfo = np.finfo(float)
+        self.assert_deprecated(lambda: getattr(finfo, "machar"))

numpy/core/tests/test_getlimits.py

@@ -46,7 +46,7 @@ def test_basic(self):
                        [np.float16, np.float32, np.float64, np.complex64,
                         np.complex128]))
         for dt1, dt2 in dts:
-            for attr in ('bits', 'eps', 'epsneg', 'iexp', 'machar', 'machep',
+            for attr in ('bits', 'eps', 'epsneg', 'iexp', 'machep',
                          'max', 'maxexp', 'min', 'minexp', 'negep', 'nexp',
                          'nmant', 'precision', 'resolution', 'tiny',
                          'smallest_normal', 'smallest_subnormal'):

numpy/core/tests/test_numeric.py

@@ -646,7 +646,7 @@ def test_floating_exceptions(self, typecode):
             if np.dtype(ftype).kind == 'f':
                 # Get some extreme values for the type
                 fi = np.finfo(ftype)
-                ft_tiny = fi.machar.tiny
+                ft_tiny = fi._machar.tiny
                 ft_max = fi.max
                 ft_eps = fi.eps
                 underflow = 'underflow'
@@ -655,7 +655,7 @@ def test_floating_exceptions(self, typecode):
                 # 'c', complex, corresponding real dtype
                 rtype = type(ftype(0).real)
                 fi = np.finfo(rtype)
-                ft_tiny = ftype(fi.machar.tiny)
+                ft_tiny = ftype(fi._machar.tiny)
                 ft_max = ftype(fi.max)
                 ft_eps = ftype(fi.eps)
                 # The complex types raise different exceptions

numpy/typing/tests/data/reveal/getlimits.pyi

@@ -1,6 +1,4 @@
 import numpy as np
-from numpy.typing import _32Bit
-
 f: float
 f8: np.float64
 c8: np.complex64
@@ -11,7 +9,6 @@ u4: np.uint32
 
 finfo_f8: np.finfo[np.float64]
 iinfo_i8: np.iinfo[np.int64]
-machar_f4: np.core.getlimits.MachArLike[_32Bit]
 
 reveal_type(np.finfo(f))  # E: numpy.finfo[{double}]
 reveal_type(np.finfo(f8))  # E: numpy.finfo[{float64}]
@@ -36,7 +33,6 @@ reveal_type(finfo_f8.resolution)  # E: {float64}
 reveal_type(finfo_f8.tiny)  # E: {float64}
 reveal_type(finfo_f8.smallest_normal)  # E: {float64}
 reveal_type(finfo_f8.smallest_subnormal)  # E: {float64}
-reveal_type(finfo_f8.machar)  # E: MachArLike[numpy.typing._64Bit]
 
 reveal_type(np.iinfo(i))  # E: iinfo[{int_}]
 reveal_type(np.iinfo(i8))  # E: iinfo[{int64}]
@@ -49,25 +45,3 @@ reveal_type(iinfo_i8.bits)  # E: int
 reveal_type(iinfo_i8.key)  # E: str
 reveal_type(iinfo_i8.min)  # E: int
 reveal_type(iinfo_i8.max)  # E: int
-
-reveal_type(machar_f4.eps)  # E: numpy.ndarray[Any, numpy.dtype[{float32}]]
-reveal_type(machar_f4.epsilon)  # E: numpy.ndarray[Any, numpy.dtype[{float32}]]
-reveal_type(machar_f4.epsneg)  # E: numpy.ndarray[Any, numpy.dtype[{float32}]]
-reveal_type(machar_f4.huge)  # E: numpy.ndarray[Any, numpy.dtype[{float32}]]
-reveal_type(machar_f4.resolution)  # E: numpy.ndarray[Any, numpy.dtype[{float32}]]
-reveal_type(machar_f4.tiny)  # E: numpy.ndarray[Any, numpy.dtype[{float32}]]
-reveal_type(machar_f4.xmax)  # E: numpy.ndarray[Any, numpy.dtype[{float32}]]
-reveal_type(machar_f4.xmin)  # E: numpy.ndarray[Any, numpy.dtype[{float32}]]
-reveal_type(machar_f4.smallest_subnormal)  # E: numpy.ndarray[Any, numpy.dtype[{float32}]]
-reveal_type(machar_f4.smallest_normal)  # E: numpy.ndarray[Any, numpy.dtype[{float32}]]
-reveal_type(machar_f4.iexp)  # E: int
-reveal_type(machar_f4.irnd)  # E: int
-reveal_type(machar_f4.it)  # E: int
-reveal_type(machar_f4.machep)  # E: int
-reveal_type(machar_f4.maxexp)  # E: int
-reveal_type(machar_f4.minexp)  # E: int
-reveal_type(machar_f4.negep)  # E: int
-reveal_type(machar_f4.ngrd)  # E: int
-reveal_type(machar_f4.precision)  # E: int
-reveal_type(machar_f4.ibeta)  # E: {int32}
-reveal_type(machar_f4.title)  # E: str