[Python-checkins] r71818 - in python/branches/py3k: Lib/test/test_complex.py Misc/NEWS Objects/complexobject.c Python/pystrtod.c
mark.dickinson
python-checkins at python.org
Thu Apr 23 21:14:16 CEST 2009
Author: mark.dickinson
Date: Thu Apr 23 21:14:16 2009
New Revision: 71818
Log:
Issue #5816: Simplify code for parsing and printing of complex numbers.
nans and infs are no longer given special treatment; as a result,
repr(complex(z)) recovers z for any complex number z.
Modified:
python/branches/py3k/Lib/test/test_complex.py
python/branches/py3k/Misc/NEWS
python/branches/py3k/Objects/complexobject.c
python/branches/py3k/Python/pystrtod.c
Modified: python/branches/py3k/Lib/test/test_complex.py
==============================================================================
--- python/branches/py3k/Lib/test/test_complex.py (original)
+++ python/branches/py3k/Lib/test/test_complex.py Thu Apr 23 21:14:16 2009
@@ -2,7 +2,7 @@
from test import support
from random import random
-from math import atan2
+from math import atan2, isnan, copysign
INF = float("inf")
NAN = float("nan")
@@ -37,6 +37,29 @@
# check that relative difference < eps
self.assert_(abs((x-y)/y) < eps)
+ def assertFloatsAreIdentical(self, x, y):
+ """assert that floats x and y are identical, in the sense that:
+ (1) both x and y are nans, or
+ (2) both x and y are infinities, with the same sign, or
+ (3) both x and y are zeros, with the same sign, or
+ (4) x and y are both finite and nonzero, and x == y
+
+ """
+ msg = 'floats {!r} and {!r} are not identical'
+
+ if isnan(x) or isnan(y):
+ if isnan(x) and isnan(y):
+ return
+ elif x == y:
+ if x != 0.0:
+ return
+ # both zero; check that signs match
+ elif copysign(1.0, x) == copysign(1.0, y):
+ return
+ else:
+ msg += ': zeros have different signs'
+ self.fail(msg.format(x, y))
+
def assertClose(self, x, y, eps=1e-9):
"""Return true iff complexes x and y "are close\""""
self.assertCloseAbs(x.real, y.real, eps)
@@ -202,6 +225,8 @@
self.assertAlmostEqual(complex("+1"), +1)
self.assertAlmostEqual(complex("(1+2j)"), 1+2j)
self.assertAlmostEqual(complex("(1.3+2.2j)"), 1.3+2.2j)
+ self.assertAlmostEqual(complex("3.14+1J"), 3.14+1j)
+ self.assertAlmostEqual(complex(" ( +3.14-6J )"), 3.14-6j)
class complex2(complex): pass
self.assertAlmostEqual(complex(complex2(1+1j)), 1+1j)
@@ -229,8 +254,6 @@
self.assertRaises(TypeError, complex, "1", "1")
self.assertRaises(TypeError, complex, 1, "1")
- self.assertEqual(complex(" 3.14+J "), 3.14+1j)
-
# SF bug 543840: complex(string) accepts strings with \0
# Fixed in 2.3.
self.assertRaises(ValueError, complex, '1+1j\0j')
@@ -254,6 +277,11 @@
self.assertRaises(ValueError, complex, "(1+2j)123")
self.assertRaises(ValueError, complex, "1"*500)
self.assertRaises(ValueError, complex, "x")
+ self.assertRaises(ValueError, complex, "J")
+ self.assertRaises(ValueError, complex, "1j+2")
+ self.assertRaises(ValueError, complex, "1e1ej")
+ self.assertRaises(ValueError, complex, "1e++1ej")
+ self.assertRaises(ValueError, complex, ")1+2j(")
class EvilExc(Exception):
pass
@@ -318,17 +346,17 @@
self.assertEqual(-6j,complex(repr(-6j)))
self.assertEqual(6j,complex(repr(6j)))
- self.assertEqual(repr(complex(1., INF)), "(1+inf*j)")
- self.assertEqual(repr(complex(1., -INF)), "(1-inf*j)")
+ self.assertEqual(repr(complex(1., INF)), "(1+infj)")
+ self.assertEqual(repr(complex(1., -INF)), "(1-infj)")
self.assertEqual(repr(complex(INF, 1)), "(inf+1j)")
- self.assertEqual(repr(complex(-INF, INF)), "(-inf+inf*j)")
+ self.assertEqual(repr(complex(-INF, INF)), "(-inf+infj)")
self.assertEqual(repr(complex(NAN, 1)), "(nan+1j)")
- self.assertEqual(repr(complex(1, NAN)), "(1+nan*j)")
- self.assertEqual(repr(complex(NAN, NAN)), "(nan+nan*j)")
+ self.assertEqual(repr(complex(1, NAN)), "(1+nanj)")
+ self.assertEqual(repr(complex(NAN, NAN)), "(nan+nanj)")
- self.assertEqual(repr(complex(0, INF)), "inf*j")
- self.assertEqual(repr(complex(0, -INF)), "-inf*j")
- self.assertEqual(repr(complex(0, NAN)), "nan*j")
+ self.assertEqual(repr(complex(0, INF)), "infj")
+ self.assertEqual(repr(complex(0, -INF)), "-infj")
+ self.assertEqual(repr(complex(0, NAN)), "nanj")
def test_neg(self):
self.assertEqual(-(1+6j), -1-6j)
@@ -367,6 +395,21 @@
self.assertEquals(atan2(z1.imag, -1.), atan2(0., -1.))
self.assertEquals(atan2(z2.imag, -1.), atan2(-0., -1.))
+ @unittest.skipUnless(float.__getformat__("double").startswith("IEEE"),
+ "test requires IEEE 754 doubles")
+ def test_repr_roundtrip(self):
+ # complex(repr(z)) should recover z exactly, even for complex numbers
+ # involving an infinity, nan, or negative zero
+ vals = [0.0, 1e-200, 0.0123, 3.1415, 1e50, INF, NAN]
+ vals += [-v for v in vals]
+ for x in vals:
+ for y in vals:
+ z = complex(x, y)
+ roundtrip = complex(repr(z))
+ self.assertFloatsAreIdentical(z.real, roundtrip.real)
+ self.assertFloatsAreIdentical(z.imag, roundtrip.imag)
+
+
def test_main():
support.run_unittest(ComplexTest)
Modified: python/branches/py3k/Misc/NEWS
==============================================================================
--- python/branches/py3k/Misc/NEWS (original)
+++ python/branches/py3k/Misc/NEWS Thu Apr 23 21:14:16 2009
@@ -12,6 +12,9 @@
Core and Builtins
-----------------
+- Issue #5816: complex(repr(z)) now recovers z exactly, even when
+ z involves nans, infs or negative zeros.
+
- Issue #3166: Make long -> float (and int -> float) conversions
correctly rounded.
Modified: python/branches/py3k/Objects/complexobject.c
==============================================================================
--- python/branches/py3k/Objects/complexobject.c (original)
+++ python/branches/py3k/Objects/complexobject.c Thu Apr 23 21:14:16 2009
@@ -332,99 +332,64 @@
static PyObject *
complex_format(PyComplexObject *v, char format_code)
{
- PyObject *result = NULL;
- Py_ssize_t len;
+ PyObject *result = NULL;
+ Py_ssize_t len;
- /* If these are non-NULL, they'll need to be freed. */
- char *pre = NULL;
- char *pim = NULL;
- char *buf = NULL;
-
- /* These do not need to be freed. They're either aliases for pim
- and pre, or pointers to constants. */
- char *re = NULL;
- char *im = NULL;
- char *lead = "";
- char *tail = "";
-
-
- if (v->cval.real == 0.) {
- re = "";
- if (!Py_IS_FINITE(v->cval.imag)) {
- if (Py_IS_NAN(v->cval.imag))
- im = "nan*";
- else if (copysign(1, v->cval.imag) == 1)
- im = "inf*";
- else
- im = "-inf*";
- }
- else {
- pim = PyOS_double_to_string(v->cval.imag, format_code,
- 0, 0, NULL);
- if (!pim) {
- PyErr_NoMemory();
- goto done;
- }
- im = pim;
- }
- } else {
- /* Format imaginary part with sign, real part without */
- if (!Py_IS_FINITE(v->cval.real)) {
- if (Py_IS_NAN(v->cval.real))
- re = "nan";
- /* else if (copysign(1, v->cval.real) == 1) */
- else if (v->cval.real > 0)
- re = "inf";
- else
- re = "-inf";
- }
- else {
- pre = PyOS_double_to_string(v->cval.real, format_code,
- 0, 0, NULL);
- if (!pre) {
- PyErr_NoMemory();
- goto done;
- }
- re = pre;
- }
-
- if (!Py_IS_FINITE(v->cval.imag)) {
- if (Py_IS_NAN(v->cval.imag))
- im = "+nan*";
- /* else if (copysign(1, v->cval.imag) == 1) */
- else if (v->cval.imag > 0)
- im = "+inf*";
- else
- im = "-inf*";
- }
- else {
- pim = PyOS_double_to_string(v->cval.imag, format_code,
- 0, Py_DTSF_SIGN, NULL);
- if (!pim) {
- PyErr_NoMemory();
- goto done;
- }
- im = pim;
- }
- lead = "(";
- tail = ")";
- }
- /* Alloc the final buffer. Add one for the "j" in the format string, and
- one for the trailing zero. */
- len = strlen(lead) + strlen(re) + strlen(im) + strlen(tail) + 2;
- buf = PyMem_Malloc(len);
- if (!buf) {
- PyErr_NoMemory();
- goto done;
- }
- PyOS_snprintf(buf, len, "%s%s%sj%s", lead, re, im, tail);
- result = PyUnicode_FromString(buf);
-done:
- PyMem_Free(pim);
- PyMem_Free(pre);
- PyMem_Free(buf);
+ /* If these are non-NULL, they'll need to be freed. */
+ char *pre = NULL;
+ char *im = NULL;
+ char *buf = NULL;
+
+ /* These do not need to be freed. re is either an alias
+ for pre or a pointer to a constant. lead and tail
+ are pointers to constants. */
+ char *re = NULL;
+ char *lead = "";
+ char *tail = "";
+
+ if (v->cval.real == 0. && copysign(1.0, v->cval.real)==1.0) {
+ re = "";
+ im = PyOS_double_to_string(v->cval.imag, format_code,
+ 0, 0, NULL);
+ if (!im) {
+ PyErr_NoMemory();
+ goto done;
+ }
+ } else {
+ /* Format imaginary part with sign, real part without */
+ pre = PyOS_double_to_string(v->cval.real, format_code,
+ 0, 0, NULL);
+ if (!pre) {
+ PyErr_NoMemory();
+ goto done;
+ }
+ re = pre;
+
+ im = PyOS_double_to_string(v->cval.imag, format_code,
+ 0, Py_DTSF_SIGN, NULL);
+ if (!im) {
+ PyErr_NoMemory();
+ goto done;
+ }
+ lead = "(";
+ tail = ")";
+ }
+ /* Alloc the final buffer. Add one for the "j" in the format string,
+ and one for the trailing zero. */
+ len = strlen(lead) + strlen(re) + strlen(im) + strlen(tail) + 2;
+ buf = PyMem_Malloc(len);
+ if (!buf) {
+ PyErr_NoMemory();
+ goto done;
+ }
+ PyOS_snprintf(buf, len, "%s%s%sj%s", lead, re, im, tail);
+ result = PyUnicode_FromString(buf);
+ done:
+ PyMem_Free(im);
+ PyMem_Free(pre);
+ PyMem_Free(buf);
- return result;
+ return result;
}
static PyObject *
@@ -757,11 +722,7 @@
const char *s, *start;
char *end;
double x=0.0, y=0.0, z;
- int got_re=0, got_im=0, got_bracket=0, done=0;
- int digit_or_dot;
- int sw_error=0;
- int sign;
- char buffer[256]; /* For errors */
+ int got_bracket=0;
char s_buffer[256];
Py_ssize_t len;
@@ -785,16 +746,13 @@
return NULL;
}
+ errno = 0;
+
/* position on first nonblank */
start = s;
while (*s && isspace(Py_CHARMASK(*s)))
s++;
- if (s[0] == '\0') {
- PyErr_SetString(PyExc_ValueError,
- "complex() arg is an empty string");
- return NULL;
- }
- if (s[0] == '(') {
+ if (*s == '(') {
/* Skip over possible bracket from repr(). */
got_bracket = 1;
s++;
@@ -802,120 +760,50 @@
s++;
}
- z = -1.0;
- sign = 1;
- do {
-
- switch (*s) {
-
- case '\0':
- if (s-start != len) {
- PyErr_SetString(
- PyExc_ValueError,
- "complex() arg contains a null byte");
- return NULL;
- }
- if(!done) sw_error=1;
- break;
-
- case ')':
- if (!got_bracket || !(got_re || got_im)) {
- sw_error=1;
- break;
- }
- got_bracket=0;
- done=1;
- s++;
- while (*s && isspace(Py_CHARMASK(*s)))
- s++;
- if (*s) sw_error=1;
- break;
-
- case '-':
- sign = -1;
- /* Fallthrough */
- case '+':
- if (done) sw_error=1;
- s++;
- if ( *s=='\0'||*s=='+'||*s=='-'||*s==')'||
- isspace(Py_CHARMASK(*s)) ) sw_error=1;
- break;
-
- case 'J':
- case 'j':
- if (got_im || done) {
- sw_error = 1;
- break;
- }
- if (z<0.0) {
- y=sign;
- }
- else{
- y=sign*z;
- }
- got_im=1;
- s++;
- if (*s!='+' && *s!='-' )
- done=1;
- break;
-
- default:
- if (isspace(Py_CHARMASK(*s))) {
- while (*s && isspace(Py_CHARMASK(*s)))
- s++;
- if (*s && *s != ')')
- sw_error=1;
- else
- done = 1;
- break;
- }
- digit_or_dot =
- (*s=='.' || isdigit(Py_CHARMASK(*s)));
- if (done||!digit_or_dot) {
- sw_error=1;
- break;
- }
- errno = 0;
- PyFPE_START_PROTECT("strtod", return 0)
- z = PyOS_ascii_strtod(s, &end) ;
- PyFPE_END_PROTECT(z)
- if (errno != 0) {
- PyOS_snprintf(buffer, sizeof(buffer),
- "float() out of range: %.150s", s);
- PyErr_SetString(
- PyExc_ValueError,
- buffer);
- return NULL;
- }
- s=end;
- if (*s=='J' || *s=='j') {
-
- break;
- }
- if (got_re) {
- sw_error=1;
- break;
- }
-
- /* accept a real part */
- x=sign*z;
- got_re=1;
- if (got_im) done=1;
- z = -1.0;
- sign = 1;
- break;
-
- } /* end of switch */
-
- } while (s - start < len && !sw_error);
-
- if (sw_error || got_bracket) {
- PyErr_SetString(PyExc_ValueError,
- "complex() arg is a malformed string");
- return NULL;
+ /* get float---might be real or imaginary part */
+ z = PyOS_ascii_strtod(s, &end);
+ if (end == s)
+ goto error;
+ s = end;
+ if (*s == '+' || *s == '-') {
+ /* we've got a real part *and* an imaginary part */
+ x = z;
+ y = PyOS_ascii_strtod(s, &end);
+ if (end == s || !(*end == 'j' || *end == 'J'))
+ goto error;
+ s = ++end;
+ }
+ else if (*s == 'j' || *s == 'J') {
+ /* no real part; z was the imaginary part */
+ s++;
+ y = z;
}
+ else
+ /* no imaginary part */
+ x = z;
+
+ /* trailing whitespace and closing bracket */
+ while (*s && isspace(Py_CHARMASK(*s)))
+ s++;
+ if (got_bracket && *s == ')') {
+ got_bracket = 0;
+ s++;
+ while (*s && isspace(Py_CHARMASK(*s)))
+ s++;
+ }
+ /* we should now be at the end of the string */
+ if (s-start != len || got_bracket)
+ goto error;
return complex_subtype_from_doubles(type, x, y);
+
+ error:
+ /* check for PyOS_ascii_strtod failure due to lack of memory */
+ if (errno == ENOMEM)
+ return PyErr_NoMemory();
+ PyErr_SetString(PyExc_ValueError,
+ "complex() arg is a malformed string");
+ return NULL;
}
static PyObject *
Modified: python/branches/py3k/Python/pystrtod.c
==============================================================================
--- python/branches/py3k/Python/pystrtod.c (original)
+++ python/branches/py3k/Python/pystrtod.c Thu Apr 23 21:14:16 2009
@@ -630,8 +630,9 @@
}
p = result;
- /* Never add sign for nan/inf, even if asked. */
- if (flags & Py_DTSF_SIGN && buf[0] != '-' && t == Py_DTST_FINITE)
+ /* Add sign when requested. It's convenient (esp. when formatting
+ complex numbers) to include a sign even for inf and nan. */
+ if (flags & Py_DTSF_SIGN && buf[0] != '-')
*p++ = '+';
strcpy(p, buf);
@@ -733,6 +734,10 @@
so convert Infinity to inf and NaN to nan, and
ignore sign of nan. Then return. */
+ /* ignore the actual sign of a nan */
+ if (digits[0] == 'n' || digits[0] == 'N')
+ sign = 0;
+
/* We only need 5 bytes to hold the result "+inf\0" . */
bufsize = 5; /* Used later in an assert. */
buf = (char *)PyMem_Malloc(bufsize);
@@ -742,13 +747,13 @@
}
p = buf;
+ if (sign == 1) {
+ *p++ = '-';
+ }
+ else if (always_add_sign) {
+ *p++ = '+';
+ }
if (digits[0] == 'i' || digits[0] == 'I') {
- if (sign == 1) {
- *p++ = '-';
- }
- else if (always_add_sign) {
- *p++ = '+';
- }
strncpy(p, float_strings[OFS_INF], 3);
p += 3;
@@ -756,8 +761,6 @@
*type = Py_DTST_INFINITE;
}
else if (digits[0] == 'n' || digits[0] == 'N') {
- /* note that we *never* add a sign for a nan,
- even if one has explicitly been requested */
strncpy(p, float_strings[OFS_NAN], 3);
p += 3;
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