I finally got the time to update and merge Mark's and my trunk-math branch. The patch is collaborated work of Mark Dickinson and me. It was mostly done a few months ago. The patch fixes a lot of loose ends and edge cases related to operations with NaN, INF, very small values and complex math.

The patch also adds acosh, asinh, atanh, log1p and copysign to all platforms. Finally it fixes differences between platforms like different results or exceptions for edge cases. Have fun :)

1 files changed, 81 insertions, 125 deletions

diff --git a/Objects/floatobject.c b/Objects/floatobject.c
index b832f7a..f79995c 100644
--- a/Objects/floatobject.c
+++ b/Objects/floatobject.c
@@ -16,10 +16,6 @@
 
 #include "formatter_string.h"
 
-#if !defined(__STDC__)
-extern double fmod(double, double);
-extern double pow(double, double);
-#endif
 
 #ifdef _OSF_SOURCE
 /* OSF1 5.1 doesn't make this available with XOPEN_SOURCE_EXTENDED defined */
@@ -251,11 +247,11 @@ PyFloat_FromString(PyObject *v, char **pend)
 			p++;
 		}
 		if (PyOS_strnicmp(p, "inf", 4) == 0) {
-			return PyFloat_FromDouble(sign * Py_HUGE_VAL);
+			Py_RETURN_INF(sign);
 		}
 #ifdef Py_NAN
 		if(PyOS_strnicmp(p, "nan", 4) == 0) {
-			return PyFloat_FromDouble(Py_NAN);
+			Py_RETURN_NAN;
 		}
 #endif
 		PyOS_snprintf(buffer, sizeof(buffer),
@@ -405,110 +401,6 @@ PyFloat_AsStringEx(char *buf, PyFloatObject *v, int precision)
 	format_float(buf, 100, v, precision);
 }
 
-#ifdef Py_BROKEN_REPR
-/* The following function is based on Tcl_PrintDouble,
- * from tclUtil.c.
- */
-
-#define is_infinite(d)	( (d) > DBL_MAX || (d) < -DBL_MAX )
-#define is_nan(d)		((d) != (d))
-
-static void
-format_double_repr(char *dst, double value)
-{
-    char *p, c;
-    int exp;
-    int signum;
-    char buffer[30];
-
-	/*
-	 * Handle NaN.
-	 */
-
-	if (is_nan(value)) {
-	    strcpy(dst, "nan");
-	    return;
-	}
-
-	/*
-	 * Handle infinities.
-	 */
-
-	if (is_infinite(value)) {
-	    if (value < 0) {
-		strcpy(dst, "-inf");
-	    } else {
-		strcpy(dst, "inf");
-	    }
-	    return;
-	}
-
-	/*
-	 * Ordinary (normal and denormal) values.
-	 */
-
-	exp = _PyFloat_Digits(buffer, value, &signum)+1;
-	if (signum) {
-	    *dst++ = '-';
-	}
-	p = buffer;
-	if (exp < -3 || exp > 17) {
-	    /*
-	     * E format for numbers < 1e-3 or >= 1e17.
-	     */
-
-	    *dst++ = *p++;
-	    c = *p;
-	    if (c != '\0') {
-		*dst++ = '.';
-		while (c != '\0') {
-		    *dst++ = c;
-		    c = *++p;
-		}
-	    }
-	    sprintf(dst, "e%+d", exp-1);
-	} else {
-	    /*
-	     * F format for others.
-	     */
-
-	    if (exp <= 0) {
-		*dst++ = '0';
-	    }
-	    c = *p;
-	    while (exp-- > 0) {
-		if (c != '\0') {
-		    *dst++ = c;
-		    c = *++p;
-		} else {
-		    *dst++ = '0';
-		}
-	    }
-	    *dst++ = '.';
-	    if (c == '\0') {
-		*dst++ = '0';
-	    } else {
-		while (++exp < 0) {
-		    *dst++ = '0';
-		}
-		while (c != '\0') {
-		    *dst++ = c;
-		    c = *++p;
-		}
-	    }
-	    *dst++ = '\0';
-	}
-}
-
-static void
-format_float_repr(char *buf, PyFloatObject *v)
-{
-	assert(PyFloat_Check(v));
-	format_double_repr(buf, PyFloat_AS_DOUBLE(v));
-}
-
-#endif /* Py_BROKEN_REPR */
-
 /* Macro and helper that convert PyObject obj to a C double and store
    the value in dbl; this replaces the functionality of the coercion
    slot function.  If conversion to double raises an exception, obj is
@@ -593,13 +485,8 @@ float_print(PyFloatObject *v, FILE *fp, int flags)
 static PyObject *
 float_repr(PyFloatObject *v)
 {
-#ifdef Py_BROKEN_REPR
-	char buf[30];
-	format_float_repr(buf, v);
-#else
 	char buf[100];
 	format_float(buf, sizeof(buf), v, PREC_REPR);
-#endif
 
 	return PyString_FromString(buf);
 }
@@ -889,10 +776,13 @@ float_div(PyObject *v, PyObject *w)
 	double a,b;
 	CONVERT_TO_DOUBLE(v, a);
 	CONVERT_TO_DOUBLE(w, b);
+#ifdef Py_NAN
 	if (b == 0.0) {
-		PyErr_SetString(PyExc_ZeroDivisionError, "float division");
+		PyErr_SetString(PyExc_ZeroDivisionError,
+				"float division");
 		return NULL;
 	}
+#endif
 	PyFPE_START_PROTECT("divide", return 0)
 	a = a / b;
 	PyFPE_END_PROTECT(a)
@@ -908,10 +798,13 @@ float_classic_div(PyObject *v, PyObject *w)
 	if (Py_DivisionWarningFlag >= 2 &&
 	    PyErr_Warn(PyExc_DeprecationWarning, "classic float division") < 0)
 		return NULL;
+#ifdef Py_NAN
 	if (b == 0.0) {
-		PyErr_SetString(PyExc_ZeroDivisionError, "float division");
+		PyErr_SetString(PyExc_ZeroDivisionError,
+				"float division");
 		return NULL;
 	}
+#endif
 	PyFPE_START_PROTECT("divide", return 0)
 	a = a / b;
 	PyFPE_END_PROTECT(a)
@@ -923,12 +816,15 @@ float_rem(PyObject *v, PyObject *w)
 {
 	double vx, wx;
 	double mod;
- 	CONVERT_TO_DOUBLE(v, vx);
- 	CONVERT_TO_DOUBLE(w, wx);
+	CONVERT_TO_DOUBLE(v, vx);
+	CONVERT_TO_DOUBLE(w, wx);
+#ifdef Py_NAN
 	if (wx == 0.0) {
-		PyErr_SetString(PyExc_ZeroDivisionError, "float modulo");
+		PyErr_SetString(PyExc_ZeroDivisionError,
+				"float modulo");
 		return NULL;
 	}
+#endif
 	PyFPE_START_PROTECT("modulo", return 0)
 	mod = fmod(vx, wx);
 	/* note: checking mod*wx < 0 is incorrect -- underflows to
@@ -1032,6 +928,9 @@ float_pow(PyObject *v, PyObject *w, PyObject *z)
 		}
 		return PyFloat_FromDouble(0.0);
 	}
+	if (iv == 1.0) { /* 1**w is 1, even 1**inf and 1**nan */
+		return PyFloat_FromDouble(1.0);
+	}
 	if (iv < 0.0) {
 		/* Whether this is an error is a mess, and bumps into libm
 		 * bugs so we have to figure it out ourselves.
@@ -1123,6 +1022,57 @@ float_coerce(PyObject **pv, PyObject **pw)
 }
 
 static PyObject *
+float_is_integer(PyObject *v)
+{
+	double x = PyFloat_AsDouble(v);
+	PyObject *o;
+	
+	if (x == -1.0 && PyErr_Occurred())
+		return NULL;
+	if (!Py_IS_FINITE(x))
+		Py_RETURN_FALSE;
+	PyFPE_START_PROTECT("is_integer", return NULL)
+	o = (floor(x) == x) ? Py_True : Py_False;
+	PyFPE_END_PROTECT(x)
+	if (errno != 0) {
+		PyErr_SetFromErrno(errno == ERANGE ? PyExc_OverflowError :
+						     PyExc_ValueError);
+		return NULL;
+	}
+	Py_INCREF(o);
+	return o;
+}
+
+#if 0
+static PyObject *
+float_is_inf(PyObject *v)
+{
+	double x = PyFloat_AsDouble(v);
+	if (x == -1.0 && PyErr_Occurred())
+		return NULL;
+	return PyBool_FromLong((long)Py_IS_INFINITY(x));
+}
+
+static PyObject *
+float_is_nan(PyObject *v)
+{
+	double x = PyFloat_AsDouble(v);
+	if (x == -1.0 && PyErr_Occurred())
+		return NULL;
+	return PyBool_FromLong((long)Py_IS_NAN(x));
+}
+
+static PyObject *
+float_is_finite(PyObject *v)
+{
+	double x = PyFloat_AsDouble(v);
+	if (x == -1.0 && PyErr_Occurred())
+		return NULL;
+	return PyBool_FromLong((long)Py_IS_FINITE(x));
+}
+#endif
+
+static PyObject *
 float_trunc(PyObject *v)
 {
 	double x = PyFloat_AsDouble(v);
@@ -1480,12 +1430,22 @@ PyDoc_STRVAR(float__format__doc,
 
 
 static PyMethodDef float_methods[] = {
-  	{"conjugate",	(PyCFunction)float_float,	METH_NOARGS,
+	{"conjugate",	(PyCFunction)float_float,	METH_NOARGS,
 	 "Returns self, the complex conjugate of any float."},
 	{"__trunc__",	(PyCFunction)float_trunc, METH_NOARGS,
          "Returns the Integral closest to x between 0 and x."},
 	{"as_integer_ratio", (PyCFunction)float_as_integer_ratio, METH_NOARGS,
 	 float_as_integer_ratio_doc},
+	{"is_integer",	(PyCFunction)float_is_integer,	METH_NOARGS,
+	 "Returns True if the float is an integer."},
+#if 0
+	{"is_inf",	(PyCFunction)float_is_inf,	METH_NOARGS,
+	 "Returns True if the float is positive or negative infinite."},
+	{"is_finite",	(PyCFunction)float_is_finite,	METH_NOARGS,
+	 "Returns True if the float is finite, neither infinite nor NaN."},
+	{"is_nan",	(PyCFunction)float_is_nan,	METH_NOARGS,
+	 "Returns True if the float is not a number (NaN)."},
+#endif
 	{"__getnewargs__",	(PyCFunction)float_getnewargs,	METH_NOARGS},
 	{"__getformat__",	(PyCFunction)float_getformat,	
 	 METH_O|METH_CLASS,		float_getformat_doc},
@@ -1646,10 +1606,6 @@ _PyFloat_Init(void)
 	double_format = detected_double_format;
 	float_format = detected_float_format;
 
-#ifdef Py_BROKEN_REPR	
-	/* Initialize floating point repr */
-	_PyFloat_DigitsInit();
-#endif
 	/* Init float info */
 	if (FloatInfoType.tp_name == 0)
 		PyStructSequence_InitType(&FloatInfoType, &floatinfo_desc);