145 lines
2.7 KiB
C
145 lines
2.7 KiB
C
|
/*
|
||
|
|
* gcvt.c - conversion for printing a floating point number
|
||
|
|
*/
|
||
|
|
/* $Header$ */
|
||
|
|
|
||
|
|
#ifndef NOFLOAT
|
||
|
|
#include "loc_incl.h"
|
||
|
|
|
||
|
|
#define NDIGINEXP(exp) (((exp) >= 100 || (exp) <= -100) ? 3 : 2)
|
||
|
|
#define LOW_EXP -4
|
||
|
|
#define USE_EXP(exp, ndigits) (((exp) < LOW_EXP + 1) || (exp >= ndigits + 1))
|
||
|
|
|
||
|
|
char *
|
||
|
|
gcvt(double value, int ndigit, char *s, int flags)
|
||
|
|
{
|
||
|
|
int sign, dp;
|
||
|
|
register char *s1, *s2;
|
||
|
|
register int i;
|
||
|
|
register int nndigit = ndigit;
|
||
|
|
|
||
|
|
s1 = ecvt(value, ndigit, &dp, &sign);
|
||
|
|
s2 = s;
|
||
|
|
if (sign) *s2++ = '-';
|
||
|
|
else if (flags & FL_SIGN)
|
||
|
|
*s2++ = '+';
|
||
|
|
else if (flags & FL_SPACE)
|
||
|
|
*s2++ = ' ';
|
||
|
|
|
||
|
|
if (!(flags & FL_ALT))
|
||
|
|
for (i = nndigit - 1; i > 0 && s1[i] == '0'; i--)
|
||
|
|
nndigit--;
|
||
|
|
|
||
|
|
if (USE_EXP(dp,ndigit)) {
|
||
|
|
/* Use E format */
|
||
|
|
dp--;
|
||
|
|
*s2++ = *s1++;
|
||
|
|
if ((nndigit > 1) || (flags & FL_ALT)) *s2++ = '.';
|
||
|
|
while (--nndigit > 0) *s2++ = *s1++;
|
||
|
|
*s2++ = 'e';
|
||
|
|
if (dp < 0) {
|
||
|
|
*s2++ = '-';
|
||
|
|
dp = -dp;
|
||
|
|
}
|
||
|
|
else *s2++ = '+';
|
||
|
|
s2 += NDIGINEXP(dp);
|
||
|
|
*s2 = 0;
|
||
|
|
for (i = NDIGINEXP(dp); i > 0; i--) {
|
||
|
|
*--s2 = dp % 10 + '0';
|
||
|
|
dp /= 10;
|
||
|
|
}
|
||
|
|
return s;
|
||
|
|
}
|
||
|
|
/* Use f format */
|
||
|
|
if (dp <= 0) {
|
||
|
|
if (*s1 != '0') {
|
||
|
|
/* otherwise the whole number is 0 */
|
||
|
|
*s2++ = '0';
|
||
|
|
*s2++ = '.';
|
||
|
|
}
|
||
|
|
while (dp < 0) {
|
||
|
|
dp++;
|
||
|
|
*s2++ = '0';
|
||
|
|
}
|
||
|
|
}
|
||
|
|
for (i = 1; i <= nndigit; i++) {
|
||
|
|
*s2++ = *s1++;
|
||
|
|
if (i == dp) *s2++ = '.';
|
||
|
|
}
|
||
|
|
if (i <= dp) {
|
||
|
|
while (i++ <= dp) *s2++ = '0';
|
||
|
|
*s2++ = '.';
|
||
|
|
}
|
||
|
|
if ((s2[-1]=='.') && !(flags & FL_ALT)) s2--;
|
||
|
|
*s2 = '\0';
|
||
|
|
return s;
|
||
|
|
}
|
||
|
|
|
||
|
|
#if EM_DSIZE != EM_LDSIZE
|
||
|
|
char *
|
||
|
|
gcvt_ldbl(long double value, int ndigit, char *s, int flags)
|
||
|
|
{
|
||
|
|
int sign, dp;
|
||
|
|
register char *s1, *s2;
|
||
|
|
register int i;
|
||
|
|
register int nndigit = ndigit;
|
||
|
|
|
||
|
|
s1 = ecvt_ldbl(value, ndigit, &dp, &sign);
|
||
|
|
s2 = s;
|
||
|
|
if (sign) *s2++ = '-';
|
||
|
|
else if (flags & FL_SIGN)
|
||
|
|
*s2++ = '+';
|
||
|
|
else if (flags & FL_SPACE)
|
||
|
|
*s2++ = ' ';
|
||
|
|
|
||
|
|
if (!(flags & FL_ALT))
|
||
|
|
for (i = nndigit - 1; i > 0 && s1[i] == '0'; i--)
|
||
|
|
nndigit--;
|
||
|
|
|
||
|
|
if (USE_EXP(dp,ndigit)) {
|
||
|
|
/* Use E format */
|
||
|
|
dp--;
|
||
|
|
*s2++ = *s1++;
|
||
|
|
if ((nndigit > 1) || (flags & FL_ALT)) *s2++ = '.';
|
||
|
|
while (--nndigit > 0) *s2++ = *s1++;
|
||
|
|
*s2++ = 'e';
|
||
|
|
if (dp < 0) {
|
||
|
|
*s2++ = '-';
|
||
|
|
dp = -dp;
|
||
|
|
}
|
||
|
|
else *s2++ = '+';
|
||
|
|
s2 += NDIGINEXP(dp);
|
||
|
|
*s2 = 0;
|
||
|
|
for (i = NDIGINEXP(dp); i > 0; i--) {
|
||
|
|
*--s2 = dp % 10 + '0';
|
||
|
|
dp /= 10;
|
||
|
|
}
|
||
|
|
return s;
|
||
|
|
}
|
||
|
|
/* Use f format */
|
||
|
|
if (dp <= 0) {
|
||
|
|
if (*s1 != '0') {
|
||
|
|
/* otherwise the whole number is 0 */
|
||
|
|
*s2++ = '0';
|
||
|
|
*s2++ = '.';
|
||
|
|
}
|
||
|
|
while (dp < 0) {
|
||
|
|
dp++;
|
||
|
|
*s2++ = '0';
|
||
|
|
}
|
||
|
|
}
|
||
|
|
for (i = 1; i <= nndigit; i++) {
|
||
|
|
*s2++ = *s1++;
|
||
|
|
if (i == dp) *s2++ = '.';
|
||
|
|
}
|
||
|
|
if (i <= dp) {
|
||
|
|
while (i++ <= dp) *s2++ = '0';
|
||
|
|
*s2++ = '.';
|
||
|
|
}
|
||
|
|
if ((s2[-1]=='.') && !(flags & FL_ALT)) s2--;
|
||
|
|
*s2 = '\0';
|
||
|
|
return s;
|
||
|
|
}
|
||
|
|
#endif /* EM_DSIZE != EM_LDSIZE */
|
||
|
|
#endif /* NOFLOAT */
|