numpy · shubham11941140 · Aug 20, 2021
diff --git a/benchmarks/benchmarks/bench_scalar.py b/benchmarks/benchmarks/bench_scalar.py
@@ -1,3 +1,4 @@
+from random import randint
 from .common import Benchmark, TYPES1
 
 import numpy as np
@@ -31,3 +32,12 @@ def time_abs(self, typename):
         n = self.num
         res = abs(abs(abs(abs(abs(abs(abs(abs(abs(abs(n))))))))))
 
+    def time_compare(self, typename):
+        n = self.num
+        res = [n == randint(-128, 127) for _ in range(10)]
+
+    def time_compare_types(self, typename):
+        n1 = self.num
+        for type_lhs in TYPES1:
+            n2 = np.dtype(type_lhs).type(randint(-128, 127))
+            res = [n1 == n2 for _ in range(10)]
diff --git a/numpy/core/src/multiarray/convert_datatype.c b/numpy/core/src/multiarray/convert_datatype.c
@@ -848,8 +848,8 @@ PyArray_CanCastScalar(PyTypeObject *from, PyTypeObject *to)
     int fromtype;
     int totype;
 
-    fromtype = _typenum_fromtypeobj((PyObject *)from, 0);
-    totype = _typenum_fromtypeobj((PyObject *)to, 0);
+    fromtype = PyArray_TypeNumFromNumPyScalarType((PyObject *)from, 0);
+    totype = PyArray_TypeNumFromNumPyScalarType((PyObject *)to, 0);
     if (fromtype == NPY_NOTYPE || totype == NPY_NOTYPE) {
         return NPY_FALSE;
     }

diff --git a/numpy/core/src/multiarray/scalarapi.c b/numpy/core/src/multiarray/scalarapi.c
@@ -443,7 +443,7 @@ NPY_NO_EXPORT PyArray_Descr *
 PyArray_DescrFromTypeObject(PyObject *type)
 {
     /* if it's a builtin type, then use the typenumber */
-    int typenum = _typenum_fromtypeobj(type,1);
+    int typenum = PyArray_TypeNumFromNumPyScalarType(type,1);
     if (typenum != NPY_NOTYPE) {
         return PyArray_DescrFromType(typenum);
     }

diff --git a/numpy/core/src/multiarray/scalartypes.c.src b/numpy/core/src/multiarray/scalartypes.c.src
@@ -4145,7 +4145,7 @@ is_anyscalar_exact(PyObject *obj)
 }
 
 NPY_NO_EXPORT int
-_typenum_fromtypeobj(PyObject *type, int user)
+PyArray_TypeNumFromNumPyScalarType(PyObject *type, int user)
 {
     int typenum, i;
 

diff --git a/numpy/core/src/multiarray/scalartypes.h b/numpy/core/src/multiarray/scalartypes.h
@@ -26,7 +26,7 @@ NPY_NO_EXPORT int
 is_anyscalar_exact(PyObject *obj);
 
 NPY_NO_EXPORT int
-_typenum_fromtypeobj(PyObject *type, int user);
+PyArray_TypeNumFromNumPyScalarType(PyObject *type, int user);
 
 NPY_NO_EXPORT void *
 scalar_value(PyObject *scalar, PyArray_Descr *descr);

@@ -16,6 +16,8 @@
 #include "numpy/ufuncobject.h"
 #include "numpy/arrayscalars.h"
 
+#include "scalartypes.h"
+
 #include "npy_import.h"
 #include "npy_pycompat.h"
 
@@ -563,6 +565,117 @@ static void
 
 /*** END OF BASIC CODE **/
 
+/**
+ * Find the descriptor for a builtin or Python numerical scalar.
+ * This function should only be used for scalar math fast paths.
+ *
+ * @param obj The object for which to find the descriptor
+ * @param descr The descriptor that was found.
+ * @returns 1 if the other object is a Python type and thus must not
+ *          handle the operation, otherwise 0. -1 _without_ an error set
+ *          if no descriptor was found.
+ */
+static int
+descr_from_basic_scalar(PyObject *obj, PyArray_Descr **descr)
+{
+    /* TODO: We could try giving defined scalars a chance... */
+    int type_num = PyArray_TypeNumFromNumPyScalarType(
+            (PyObject *)Py_TYPE(obj), 0);
+    if (type_num != NPY_NOTYPE) {
+        *descr = PyArray_DescrFromType(type_num);
+        return 0;
+    }
+    else if (PyFloat_CheckExact(obj)) {
+        *descr = PyArray_DescrFromType(NPY_DOUBLE);
+        return 1;
+    }
+    else if (PyBool_Check(obj)) {
+        *descr = PyArray_DescrFromType(NPY_BOOL);
+        return 1;
+    }
+    else if (PyLong_CheckExact(obj)) {
+        if (PyLong_AsLong(obj) == -1 && PyErr_Occurred()) {
+            PyErr_Clear();
+            return -1;
+            }
+        *descr = PyArray_DescrFromType(NPY_LONG);
+        return 1;
+    }
+    else if (PyComplex_CheckExact(obj)) {
+        *descr = PyArray_DescrFromType(NPY_CDOUBLE);
+        return 1;
+    }
+    return -1;
+}
+
+#define PyDescr_PythonRepresentable(d) (d->type_num < NPY_LONGDOUBLE || \
+        d->type_num == NPY_CFLOAT || d->type_num == NPY_CDOUBLE)
+
+/**
+ * This function attempts to compare NumPy or Python scalars
+ * The operation is done by getting value of both scalars
+ * and calling richcompare on them.
+  *
+ * @param self The first object which will be converted to scalar item
+ * @param other The second object to compare to
+ * @param cmp_op The value of comparison operator
+ * @returns Py_False or Py_True if richcompare is successfull
+ *          , otherwise NULL.
+ */
+static PyObject*
+do_richcompare_on_scalars(PyObject *self, PyObject *other, int cmp_op) {
+    PyObject *cmp_item_self, *cmp_item_other, *ret=NULL;
+    PyArray_Descr *self_descr=NULL, *other_descr=NULL;
+    void *data_self, *data_other;
+    int pyscalar_other, pyscalar_self;
+    int is_complex_operands, is_equality_operator, is_python_representable;
+
+    pyscalar_self = descr_from_basic_scalar(self, &self_descr);
+    pyscalar_other = descr_from_basic_scalar(other, &other_descr);
+
+    if (pyscalar_self >= 0 && pyscalar_other >= 0) {
+        /*
+         * If either of the operands are complex and operator is not equality,
+         * or the operands are not representable as a native type,
+         * python's built-in richcompare cannot be used as it is not supported.
+         */
+        is_complex_operands = (PyTypeNum_ISCOMPLEX(self_descr->type_num) ||
+            PyTypeNum_ISCOMPLEX(other_descr->type_num));
+        is_equality_operator = (cmp_op != Py_EQ && cmp_op != Py_NE);
+        is_python_representable = PyDescr_PythonRepresentable(self_descr) &&
+            PyDescr_PythonRepresentable(other_descr);
+
+        if (!(is_complex_operands && is_equality_operator) && is_python_representable) {
+            /*
+             * If the scalar is a python built-in, we can use the object as is.
+             * Else we need to obtain the value from the operand.
+             * Note: If we reach this point, one of the scalars must be built-in.
+             */
+            data_self = scalar_value(self, NULL);
+            data_other = scalar_value(other, NULL);
+            cmp_item_self = pyscalar_self == 0 ? self_descr->f->getitem(data_self, NULL):
+                self;
+            cmp_item_other = pyscalar_other == 0 ? other_descr->f->getitem(data_other, NULL):
+                other;
+
+            if (cmp_item_self != NULL && cmp_item_other != NULL) {
+                ret = PyObject_RichCompare(cmp_item_self, cmp_item_other, cmp_op);
+            }
+
+            if (pyscalar_self == 0) {
+                Py_XDECREF(cmp_item_self);
+            }
+            if (pyscalar_other == 0) {
+                Py_XDECREF(cmp_item_other);
+            }
+        }
+    }
+    Py_XDECREF(self_descr);
+    Py_XDECREF(other_descr);
+
+    return ret;
+}
+
 
 /* The general strategy for commutative binary operators is to
  *
@@ -581,86 +694,39 @@ static void
 /**begin repeat
  * #name = byte, ubyte, short, ushort, int, uint,
  *         long, ulong, longlong, ulonglong,
- *         half, float, longdouble,
+ *         half, float, double, longdouble,
  *         cfloat, cdouble, clongdouble#
  * #type = npy_byte, npy_ubyte, npy_short, npy_ushort, npy_int, npy_uint,
  *         npy_long, npy_ulong, npy_longlong, npy_ulonglong,
- *         npy_half, npy_float, npy_longdouble,
+ *         npy_half, npy_float, npy_double, npy_longdouble,
  *         npy_cfloat, npy_cdouble, npy_clongdouble#
  * #Name = Byte, UByte, Short, UShort, Int, UInt,
  *         Long, ULong, LongLong, ULongLong,
- *         Half, Float, LongDouble,
+ *         Half, Float, Double, LongDouble,
  *         CFloat, CDouble, CLongDouble#
  * #TYPE = NPY_BYTE, NPY_UBYTE, NPY_SHORT, NPY_USHORT, NPY_INT, NPY_UINT,
  *         NPY_LONG, NPY_ULONG, NPY_LONGLONG, NPY_ULONGLONG,
- *         NPY_HALF, NPY_FLOAT, NPY_LONGDOUBLE,
+ *         NPY_HALF, NPY_FLOAT, NPY_DOUBLE, NPY_LONGDOUBLE,
  *         NPY_CFLOAT, NPY_CDOUBLE, NPY_CLONGDOUBLE#
  */
 
-static int
-_@name@_convert_to_ctype(PyObject *a, @type@ *arg1)
-{
-    PyObject *temp;
 
-    if (PyArray_IsScalar(a, @Name@)) {
-        *arg1 = PyArrayScalar_VAL(a, @Name@);
-        return 0;
-    }
-    else if (PyArray_IsScalar(a, Generic)) {
-        PyArray_Descr *descr1;
-
-        if (!PyArray_IsScalar(a, Number)) {
-            return -1;
-        }
-        descr1 = PyArray_DescrFromTypeObject((PyObject *)Py_TYPE(a));
-        if (PyArray_CanCastSafely(descr1->type_num, @TYPE@)) {
-            PyArray_CastScalarDirect(a, descr1, arg1, @TYPE@);
-            Py_DECREF(descr1);
-            return 0;
-        }
-        else {
-            Py_DECREF(descr1);
-            return -1;
-        }
-    }
-    else if (PyArray_GetPriority(a, NPY_PRIORITY) > NPY_PRIORITY) {
-        return -2;
-    }
-    else if ((temp = PyArray_ScalarFromObject(a)) != NULL) {
-        int retval = _@name@_convert_to_ctype(temp, arg1);
-
-        Py_DECREF(temp);
-        return retval;
-    }
-    return -2;
-}
-
-/**end repeat**/
-
-
-/* Same as above but added exact checks against known python types for speed */
-
-/**begin repeat
- * #name = double#
- * #type = npy_double#
- * #Name = Double#
- * #TYPE = NPY_DOUBLE#
- * #PYCHECKEXACT = PyFloat_CheckExact#
- * #PYEXTRACTCTYPE = PyFloat_AS_DOUBLE#
- */
+#define _IS_@Name@
 
 static int
-_@name@_convert_to_ctype(PyObject *a, @type@ *arg1)
+_@name@_convert_to_ctype(PyObject *a, @type@ *arg)
 {
     PyObject *temp;
 
-    if (@PYCHECKEXACT@(a)){
-        *arg1 = @PYEXTRACTCTYPE@(a);
+#if defined(_IS_Double) || defined(_IS_LongDouble)
+    if (PyFloat_CheckExact(a)) {
+        *arg = (@type@)PyFloat_AS_DOUBLE(a);
         return 0;
     }
+#endif
 
     if (PyArray_IsScalar(a, @Name@)) {
-        *arg1 = PyArrayScalar_VAL(a, @Name@);
+        *arg = PyArrayScalar_VAL(a, @Name@);
         return 0;
     }
     else if (PyArray_IsScalar(a, Generic)) {
@@ -671,7 +737,7 @@ _@name@_convert_to_ctype(PyObject *a, @type@ *arg1)
         }
         descr1 = PyArray_DescrFromTypeObject((PyObject *)Py_TYPE(a));
         if (PyArray_CanCastSafely(descr1->type_num, @TYPE@)) {
-            PyArray_CastScalarDirect(a, descr1, arg1, @TYPE@);
+            PyArray_CastScalarDirect(a, descr1, arg, @TYPE@);
             Py_DECREF(descr1);
             return 0;
         }
@@ -684,14 +750,16 @@ _@name@_convert_to_ctype(PyObject *a, @type@ *arg1)
         return -2;
     }
     else if ((temp = PyArray_ScalarFromObject(a)) != NULL) {
-        int retval = _@name@_convert_to_ctype(temp, arg1);
+        int retval = _@name@_convert_to_ctype(temp, arg);
 
         Py_DECREF(temp);
         return retval;
     }
     return -2;
 }
 
+#undef _IS_@Name@
+
 /**end repeat**/
 
 
@@ -1048,11 +1116,11 @@ static PyObject *
  *
  */
 
-/* 
-Complex numbers do not support remainder operations. Unfortunately, 
-the type inference for long doubles is complicated, and if a remainder 
-operation is not defined - if the relevant field is left NULL - then 
-operations between long doubles and objects lead to an infinite recursion 
+/*
+Complex numbers do not support remainder operations. Unfortunately,
+the type inference for long doubles is complicated, and if a remainder
+operation is not defined - if the relevant field is left NULL - then
+operations between long doubles and objects lead to an infinite recursion
 instead of a TypeError. This should ensure that once everything gets
 converted to complex long doubles you correctly get a reasonably
 informative TypeError. This fixes the last part of bug gh-18548.
@@ -1359,14 +1427,20 @@ static PyObject*
 {
     npy_@name@ arg1, arg2;
     int out=0;
+    PyObject *ret;
 
     RICHCMP_GIVE_UP_IF_NEEDED(self, other);
 
     switch(_@name@_convert2_to_ctypes(self, &arg1, other, &arg2)) {
     case 0:
         break;
     case -1:
-        /* can't cast both safely use different add function */
+        /* can't cast both safely to same type.
+         * Try fastpath else use ufuncs */
+        ret = do_richcompare_on_scalars(self, other, cmp_op);
+        if (ret != NULL) {
+            return ret;
+        }
     case -2:
         /* use ufunc */
         if (PyErr_Occurred()) {