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-
+
-
-
+
+
-
+
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* None.
*
*----------------------------------------------------------------------
*/
double
strtod(
CONST char *string, /* A decimal ASCII floating-point number,
const char *string, /* A decimal ASCII floating-point number,
* optionally preceded by white space. Must
* have form "-I.FE-X", where I is the integer
* part of the mantissa, F is the fractional
* part of the mantissa, and X is the
* exponent. Either of the signs may be "+",
* "-", or omitted. Either I or F may be
* omitted, or both. The decimal point isn't
* necessary unless F is present. The "E" may
* actually be an "e". E and X may both be
* omitted (but not just one). */
char **endPtr) /* If non-NULL, store terminating character's
* address here. */
{
int sign, expSign = FALSE;
double fraction, dblExp, *d;
register CONST char *p;
register int c;
const char *p;
int c;
int exp = 0; /* Exponent read from "EX" field. */
int fracExp = 0; /* Exponent that derives from the fractional
* part. Under normal circumstatnces, it is
* the negative of the number of digits in F.
* However, if I is very long, the last digits
* of I get dropped (otherwise a long I with a
* large negative exponent could cause an
* unnecessary overflow on I alone). In this
* case, fracExp is incremented one for each
* dropped digit. */
int mantSize; /* Number of digits in mantissa. */
int decPt; /* Number of mantissa digits BEFORE decimal
* point. */
CONST char *pExp; /* Temporarily holds location of exponent in
const char *pExp; /* Temporarily holds location of exponent in
* string. */
/*
* Strip off leading blanks and check for a sign.
*/
p = string;
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/*
* Now suck up the digits in the mantissa. Use two integers to collect 9
* digits each (this is faster than using floating-point). If the mantissa
* has more than 18 digits, ignore the extras, since they can't affect the
* value anyway.
*/
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}
/*
* Generate a floating-point number that represents the exponent. Do this
* by processing the exponent one bit at a time to combine many powers of
* 2 of 10. Then combine the exponent with the fraction.
*/
|