Remove ilog2().

Author: serhiy-storchaka

Doc/library/intmath.rst

@@ -49,16 +49,6 @@ integers.
    returns ``0``.
 
 
-.. function:: ilog2(n)
-
-   Return the integer base 2 logarithm of the positive integer *n*. This is the
-   floor of the exact base 2 logarithm root of *n*, or equivalently the
-   greatest integer *k* such that
-   2\ :sup:`k` |nbsp| ≤ |nbsp| *n* |nbsp| < |nbsp| 2\ :sup:`k+1`.
-
-   It is equivalent to ``n.bit_length() - 1`` for positive *n*.
-
-
 .. function:: isqrt(n)
 
    Return the integer square root of the nonnegative integer *n*. This is the

Lib/test/test_intmath.py

@@ -200,25 +200,6 @@ def test_lcm(self):
         self.assertRaises(TypeError, lcm, 120, 0, 84.0)
         self.assertEqual(lcm(MyIndexable(120), MyIndexable(84)), 840)
 
-    def test_ilog2(self):
-        ilog2 = self.module.ilog2
-        for value in range(1, 1000):
-            k = ilog2(value)
-            self.assertLessEqual(2**k, value)
-            self.assertLess(value, 2**(k+1))
-        self.assertRaises(ValueError, ilog2, 0)
-        self.assertRaises(ValueError, ilog2, -1)
-        self.assertRaises(ValueError, ilog2, -2**1000)
-
-        self.assertIntEqual(ilog2(True), 0)
-        self.assertIntEqual(ilog2(IntSubclass(5)), 2)
-        self.assertIntEqual(ilog2(MyIndexable(5)), 2)
-
-        self.assertRaises(TypeError, ilog2, 5.0)
-        self.assertRaises(TypeError, ilog2, Decimal('5'))
-        self.assertRaises(TypeError, ilog2, Fraction(5, 1))
-        self.assertRaises(TypeError, ilog2, '5')
-
     def test_isqrt(self):
         isqrt = self.module.isqrt
         # Test a variety of inputs, large and small.
@@ -405,7 +386,6 @@ def test_comb(self):
 
 class MathTests(IntMathTests):
     import math as module
-    test_ilog2 = None
 
 
 if __name__ == '__main__':

Modules/clinic/intmathmodule.c.h

@@ -151,43 +151,6 @@ intmath_lcm_impl(PyObject *module, PyObject * const *args,
 }
 
 
-/*[clinic input]
-intmath.ilog2
-
-    n: object
-    /
-
-Return the integer part of the base 2 logarithm of the input.
-[clinic start generated code]*/
-
-static PyObject *
-intmath_ilog2(PyObject *module, PyObject *n)
-/*[clinic end generated code: output=5cd0b0553370e109 input=bf17dd4e720e922e]*/
-{
-    int64_t bits;
-
-    n = PyNumber_Index(n);
-    if (n == NULL) {
-        return NULL;
-    }
-
-    if (!_PyLong_IsPositive((PyLongObject *)n)) {
-        PyErr_SetString(
-            PyExc_ValueError,
-            "ilog2() argument must be positive");
-        Py_DECREF(n);
-        return NULL;
-    }
-
-    bits = _PyLong_NumBits(n);
-    Py_DECREF(n);
-    if (bits == -1) {
-        return NULL;
-    }
-    return PyLong_FromInt64(bits - 1);
-}
-
-
 /* Integer square root
 
 Given a nonnegative integer `n`, we want to compute the largest integer
@@ -1270,7 +1233,6 @@ static PyMethodDef intmath_methods[] = {
     INTMATH_COMB_METHODDEF
     INTMATH_FACTORIAL_METHODDEF
     INTMATH_GCD_METHODDEF
-    INTMATH_ILOG2_METHODDEF
     INTMATH_ISQRT_METHODDEF
     INTMATH_LCM_METHODDEF
     INTMATH_PERM_METHODDEF