[Python-checkins] r70759 - in python/branches/py3k-short-float-repr: Include/pystrtod.h Objects/floatobject.c Python/pystrtod.c Python/strtod.c

eric.smith python-checkins at python.org
Mon Mar 30 23:53:56 CEST 2009


Author: eric.smith
Date: Mon Mar 30 23:53:55 2009
New Revision: 70759

Log:
Hooked up new float formats to float's str(); deleted unused strtod.c.

Removed:
   python/branches/py3k-short-float-repr/Python/strtod.c
Modified:
   python/branches/py3k-short-float-repr/Include/pystrtod.h
   python/branches/py3k-short-float-repr/Objects/floatobject.c
   python/branches/py3k-short-float-repr/Python/pystrtod.c

Modified: python/branches/py3k-short-float-repr/Include/pystrtod.h
==============================================================================
--- python/branches/py3k-short-float-repr/Include/pystrtod.h	(original)
+++ python/branches/py3k-short-float-repr/Include/pystrtod.h	Mon Mar 30 23:53:55 2009
@@ -9,6 +9,13 @@
 PyAPI_FUNC(double) PyOS_ascii_strtod(const char *str, char **ptr);
 PyAPI_FUNC(double) PyOS_ascii_atof(const char *str);
 PyAPI_FUNC(char *) PyOS_ascii_formatd(char *buffer, size_t buf_len,  const char *format, double d);
+PyAPI_FUNC(char *) PyOS_double_to_string(double val,
+                                         int mode,
+                                         char format_code,
+                                         int precision,
+                                         int sign,
+                                         int add_dot_0_if_integer);
+
 
 
 #ifdef __cplusplus

Modified: python/branches/py3k-short-float-repr/Objects/floatobject.c
==============================================================================
--- python/branches/py3k-short-float-repr/Objects/floatobject.c	(original)
+++ python/branches/py3k-short-float-repr/Objects/floatobject.c	Mon Mar 30 23:53:55 2009
@@ -379,101 +379,6 @@
 
 }
 
-/* convert a Python float to a minimal string that evaluates back to that
-   float.  The output is minimal in the sense of having the least possible
-   number of significant digits. */
-
-static void
-format_float_short(char *buf, size_t buflen, PyFloatObject *v)
-{
-	double d;
-	char *digits, *digits_end;
-	int decpt, sign, exp_len;
-	size_t digits_len, i;
-
-	assert(PyFloat_Check(v));
-	d = PyFloat_AS_DOUBLE(v);
-
-	/* _Py_dg_dtoa returns a digit string (no decimal point
-	   or exponent) */
-	digits = _Py_dg_dtoa(d, 0, 0, &decpt, &sign, &digits_end);
-	assert(digits_end != NULL && digits_end > digits);
-	digits_len = digits_end - digits;
-
-	if (!isdigit(digits[0])) {
-		/* infinities and nans here; adapt Gay's output,
-		   so convert Infinity to inf and NaN to nan, and
-		   ignore sign of nan. */
-		if (digits[0] == 'i' || digits[0] == 'I') {
-			if (sign == 1) {
-				*buf++ = '-';
-			}
-			strncpy(buf, "inf", 3);
-			buf += 3;
-		} else {
-			assert(digits[0] == 'n' || digits[0] == 'N');
-			strncpy(buf, "nan", 3);
-			buf += 3;
-		}
-	}
-	else if (-4 < decpt && decpt <= 17) {
-		if (sign == 1) {
-			*buf++ = '-';
-		}
-		/* use fixed-point notation if 1e-4 <= value < 1e17 */
-		if (decpt <= 0) {
-			/* output: 0.00...00dd...dd */
-			*buf++ = '0';
-			*buf++ = '.';
-			for (i=0; i < -decpt; i++)
-				*buf++ = '0';
-			strncpy(buf, digits, digits_len);
-			buf += digits_len;
-		}
-		else if (decpt < digits_len) {
-			/* output: dd...dd.dd...dd */
-			strncpy(buf, digits, decpt);
-			buf += decpt;
-			*buf++ = '.';
-			strncpy(buf, digits+decpt, digits_len-decpt);
-			buf += digits_len-decpt;
-		}
-		else {
-			/* decpt >= digits_len.  output: dd...dd00...00.0 */
-			strncpy(buf, digits, digits_len);
-			buf += digits_len;
-			for (i=0; i < decpt-digits_len; i++)
-				*buf++ = '0';
-			*buf++ = '.';
-			*buf++ = '0';
-		}
-	}
-	else {
-		/* exponential notation: d[.dddd]e(+|-)ee;
-		   at least 2 digits in exponent */
-		if (sign == 1) {
-			*buf++ = '-';
-		}
-		*buf++ = digits[0];
-		if (digits_len > 1) {
-			*buf++ = '.';
-			strncpy(buf, digits+1, digits_len-1);
-			buf += digits_len-1;
-		}
-		*buf++ = 'e';
-		exp_len = sprintf(buf, "%+.02d", decpt-1);
-		buf += exp_len;
-	}
-	*buf++ = '\0';
-}
-
-static void
-format_float(char *buf, size_t buflen, PyFloatObject *v, int precision)
-{
-	assert(PyFloat_Check(v));
-	format_double(buf, buflen, PyFloat_AS_DOUBLE(v), precision);
-}
-
 /* Macro and helper that convert PyObject obj to a C double and store
    the value in dbl.  If conversion to double raises an exception, obj is
    set to NULL, and the function invoking this macro returns NULL.  If
@@ -524,20 +429,29 @@
 #define PREC_STR	12
 
 static PyObject *
-float_repr(PyFloatObject *v)
+float_str_or_repr(PyFloatObject *v, int mode, int precision)
 {
-	char buf[100];
-	format_float_short(buf, sizeof(buf), v);
+    PyObject *result;
+    char *buf = PyOS_double_to_string(PyFloat_AS_DOUBLE(v),
+                                      mode, 'g', precision, 0, 1);
+    if (!buf)
+        return PyErr_NoMemory();
+    result = PyUnicode_FromString(buf);
+    PyMem_Free(buf);
+    return result;
+}
 
-	return PyUnicode_FromString(buf);
+static PyObject *
+float_repr(PyFloatObject *v)
+{
+    /* XXX change PREC_REPR to 0 when mode is supported */
+    return float_str_or_repr(v, 0, PREC_REPR);
 }
 
 static PyObject *
 float_str(PyFloatObject *v)
 {
-	char buf[100];
-	format_float(buf, sizeof(buf), v, PREC_STR);
-	return PyUnicode_FromString(buf);
+    return float_str_or_repr(v, 2, PREC_STR);
 }
 
 /* Comparison is pretty much a nightmare.  When comparing float to float,
@@ -2067,7 +1981,9 @@
 				if (PyFloat_CheckExact(p) &&
 				    Py_REFCNT(p) != 0) {
 					char buf[100];
-					format_float(buf, sizeof(buf), p, PREC_STR);
+					format_double(buf, sizeof(buf),
+                                                      PyFloat_AS_DOUBLE(p),
+                                                      PREC_STR);
 					/* XXX(twouters) cast refcount to
 					   long until %zd is universally
 					   available

Modified: python/branches/py3k-short-float-repr/Python/pystrtod.c
==============================================================================
--- python/branches/py3k-short-float-repr/Python/pystrtod.c	(original)
+++ python/branches/py3k-short-float-repr/Python/pystrtod.c	Mon Mar 30 23:53:55 2009
@@ -488,3 +488,128 @@
 {
 	return PyOS_ascii_strtod(nptr, NULL);
 }
+
+
+/* convert a Python float to a minimal string that evaluates back to that
+   float.  The output is minimal in the sense of having the least possible
+   number of significant digits. */
+
+static void
+format_float_short(char *buf, size_t buflen, double d, int mode, int precision)
+{
+	char *digits, *digits_end;
+	int decpt, sign, exp_len;
+	size_t digits_len, i;
+
+	/* _Py_dg_dtoa returns a digit string (no decimal point
+	   or exponent) */
+	digits = _Py_dg_dtoa(d, mode, precision, &decpt, &sign, &digits_end);
+	assert(digits_end != NULL && digits_end > digits);
+	digits_len = digits_end - digits;
+
+	if (!isdigit(digits[0])) {
+		/* infinities and nans here; adapt Gay's output,
+		   so convert Infinity to inf and NaN to nan, and
+		   ignore sign of nan. */
+		if (digits[0] == 'i' || digits[0] == 'I') {
+			if (sign == 1) {
+				*buf++ = '-';
+			}
+			strncpy(buf, "inf", 3);
+			buf += 3;
+		} else {
+			assert(digits[0] == 'n' || digits[0] == 'N');
+			strncpy(buf, "nan", 3);
+			buf += 3;
+		}
+	}
+	else if (-4 < decpt && decpt <= 17) {
+		if (sign == 1) {
+			*buf++ = '-';
+		}
+		/* use fixed-point notation if 1e-4 <= value < 1e17 */
+		if (decpt <= 0) {
+			/* output: 0.00...00dd...dd */
+			*buf++ = '0';
+			*buf++ = '.';
+			for (i=0; i < -decpt; i++)
+				*buf++ = '0';
+			strncpy(buf, digits, digits_len);
+			buf += digits_len;
+		}
+		else if (decpt < digits_len) {
+			/* output: dd...dd.dd...dd */
+			strncpy(buf, digits, decpt);
+			buf += decpt;
+			*buf++ = '.';
+			strncpy(buf, digits+decpt, digits_len-decpt);
+			buf += digits_len-decpt;
+		}
+		else {
+			/* decpt >= digits_len.  output: dd...dd00...00.0 */
+			strncpy(buf, digits, digits_len);
+			buf += digits_len;
+			for (i=0; i < decpt-digits_len; i++)
+				*buf++ = '0';
+			*buf++ = '.';
+			*buf++ = '0';
+		}
+	}
+	else {
+		/* exponential notation: d[.dddd]e(+|-)ee;
+		   at least 2 digits in exponent */
+		if (sign == 1) {
+			*buf++ = '-';
+		}
+		*buf++ = digits[0];
+		if (digits_len > 1) {
+			*buf++ = '.';
+			strncpy(buf, digits+1, digits_len-1);
+			buf += digits_len-1;
+		}
+		*buf++ = 'e';
+		exp_len = sprintf(buf, "%+.02d", decpt-1);
+		buf += exp_len;
+	}
+	*buf++ = '\0';
+}
+
+PyAPI_FUNC(char *) PyOS_double_to_string(double val,
+                                         int mode,
+                                         char format_code,
+                                         int precision,
+                                         int sign,
+                                         int add_dot_0_if_integer)
+{
+	char fmt[32];
+	char* buf = (char *)PyMem_Malloc(512);
+
+//	printf("in PyOS_double_to_string\n");
+	if (!buf)
+		return NULL;
+
+	/* XXX validate format_code */
+
+	format_float_short(buf, 512, val, mode, precision);
+
+	if (add_dot_0_if_integer) {
+		/* If the result was just an integer, without a decimal, then
+		   add ".0" to the end of the string. */
+		char *cp = buf;
+		if (*cp == '-')
+			cp++;
+		for (; *cp != '\0'; cp++) {
+			/* Any non-digit means it's not an integer;
+			   this takes care of NAN and INF as well. */
+			if (!isdigit(Py_CHARMASK(*cp)))
+				break;
+		}
+		if (*cp == '\0') {
+			*cp++ = '.';
+			*cp++ = '0';
+			*cp++ = '\0';
+		}
+	}
+
+	return buf;
+}

Deleted: python/branches/py3k-short-float-repr/Python/strtod.c
==============================================================================
--- python/branches/py3k-short-float-repr/Python/strtod.c	Mon Mar 30 23:53:55 2009
+++ (empty file)
@@ -1,156 +0,0 @@
-#include "pyconfig.h"
-
-/* comp.sources.misc strtod(), as posted in comp.lang.tcl,
-   with bugfix for "123000.0" and acceptance of space after 'e' sign nuked.
-
-   ************************************************************
-   * YOU MUST EDIT THE MACHINE-DEPENDENT DEFINITIONS BELOW!!! *
-   ************************************************************
-*/
-
-/*  File   : stdtod.c (Modified version of str2dbl.c)
-    Author : Richard A. O'Keefe @ Quintus Computer Systems, Inc.
-    Updated: Tuesday August 2nd, 1988
-    Defines: double strtod (char *str, char**ptr)
-*/
-
-/*  This is an implementation of the strtod() function described in the 
-    System V manuals, with a different name to avoid linker problems.
-    All that str2dbl() does itself is check that the argument is well-formed
-    and is in range.  It leaves the work of conversion to atof(), which is
-    assumed to exist and deliver correct results (if they can be represented).
-
-    There are two reasons why this should be provided to the net:
-    (a) some UNIX systems do not yet have strtod(), or do not have it
-        available in the BSD "universe" (but they do have atof()).
-    (b) some of the UNIX systems that *do* have it get it wrong.
-	(some crash with large arguments, some assign the wrong *ptr value).
-    There is a reason why *we* are providing it: we need a correct version
-    of strtod(), and if we give this one away maybe someone will look for
-    mistakes in it and fix them for us (:-).
-*/
-    
-/*  The following constants are machine-specific.  MD{MIN,MAX}EXPT are
-    integers and MD{MIN,MAX}FRAC are strings such that
-	0.${MDMAXFRAC}e${MDMAXEXPT} is the largest representable double,
-	0.${MDMINFRAC}e${MDMINEXPT} is the smallest representable +ve double
-    MD{MIN,MAX}FRAC must not have any trailing zeros.
-    The values here are for IEEE-754 64-bit floats.
-    It is not perfectly clear to me whether an IEEE infinity should be
-    returned for overflow, nor what a portable way of writing one is,
-    so HUGE is just 0.MAXFRAC*10**MAXEXPT (this seems still to be the
-    UNIX convention).
-
-    I do know about <values.h>, but the whole point of this file is that
-    we can't always trust that stuff to be there or to be correct.
-*/
-static	int	MDMINEXPT	= -323;
-static	char	MDMINFRAC[]	= "494065645841246544";
-static	double	ZERO		= 0.0;
-
-static	int	MDMAXEXPT	= 309;
-static	char	MDMAXFRAC[]	= "17976931348623157";
-static	double	HUGE		= 1.7976931348623157e308;
-
-extern	double	atof(const char *);		/* Only called when result known to be ok */
-
-#ifdef HAVE_ERRNO_H
-#include <errno.h>
-#endif
-extern	int	errno;
-
-double strtod(char *str, char **ptr)
-{
-	int sign, scale, dotseen;
-	int esign, expt;
-	char *save;
-	register char *sp, *dp;
-	register int c;
-	char *buforg, *buflim;
-	char buffer[64];		/* 45-digit significant + */
-					/* 13-digit exponent */
-	sp = str;
-	while (*sp == ' ') sp++;
-	sign = 1;
-	if (*sp == '-') sign -= 2, sp++;
-	dotseen = 0, scale = 0;
-	dp = buffer;	
-	*dp++ = '0'; *dp++ = '.';
-	buforg = dp, buflim = buffer+48;
-	for (save = sp; c = *sp; sp++)
-	    if (c == '.') {
-		if (dotseen) break;
-		dotseen++;
-	    } else
-	    if ((unsigned)(c-'0') > (unsigned)('9'-'0')) {
-		break;
-	    } else
-	    if (c == '0') {
-		if (dp != buforg) {
-		    /* This is not the first digit, so we want to keep it */
-		    if (dp < buflim) *dp++ = c;
-		    if (!dotseen) scale++;
-		} else {
-		    /* No non-zero digits seen yet */
-		    /* If a . has been seen, scale must be adjusted */
-		    if (dotseen) scale--;
-		}
-	    } else {
-		/* This is a nonzero digit, so we want to keep it */
-		if (dp < buflim) *dp++ = c;
-		/* If it precedes a ., scale must be adjusted */
-		if (!dotseen) scale++;
-	    }
-	if (sp == save) {
-	    if (ptr) *ptr = str;
-	    errno = EDOM;		/* what should this be? */
-	    return ZERO;
-	}
-	
-	while (dp > buforg && dp[-1] == '0') --dp;
-	if (dp == buforg) *dp++ = '0';
-	*dp = '\0';
-	/*  Now the contents of buffer are
-	    +--+--------+-+--------+
-	    |0.|fraction|\|leftover|
-	    +--+--------+-+--------+
-			 ^dp points here
-	    where fraction begins with 0 iff it is "0", and has at most
-	    45 digits in it, and leftover is at least 16 characters.
-	*/
-	save = sp, expt = 0, esign = 1;
-	do {
-	    c = *sp++;
-	    if (c != 'e' && c != 'E') break;
-	    c = *sp++;
-	    if (c == '-') esign -= 2, c = *sp++; else
-	    if (c == '+' /* || c == ' ' */ ) c = *sp++;
-	    if ((unsigned)(c-'0') > (unsigned)('9'-'0')) break;
-	    while (c == '0') c = *sp++;
-	    for (; (unsigned)(c-'0') <= (unsigned)('9'-'0'); c = *sp++)
-		expt = expt*10 + c-'0';	    
-	    if (esign < 0) expt = -expt;
-	    save = sp-1;
-	} while (0);
-	if (ptr) *ptr = save;
-	expt += scale;
-	/*  Now the number is sign*0.fraction*10**expt  */
-	errno = ERANGE;
-	if (expt > MDMAXEXPT) {
-	    return HUGE*sign;
-	} else
-	if (expt == MDMAXEXPT) {
-	    if (strcmp(buforg, MDMAXFRAC) > 0) return HUGE*sign;
-	} else
-	if (expt < MDMINEXPT) {
-	    return ZERO*sign;
-	} else
-	if (expt == MDMINEXPT) {
-	    if (strcmp(buforg, MDMINFRAC) < 0) return ZERO*sign;
-	}
-	/*  We have now established that the number can be  */
-	/*  represented without overflow or underflow  */
-	(void) sprintf(dp, "E%d", expt);
-	errno = 0;
-	return atof(buffer)*sign;
-}


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