Return to set_str_raw.c CVS log

Up to [local] / OpenXM_contrib / gmp / mpfr

Annotation of OpenXM_contrib/gmp/mpfr/set_str_raw.c, Revision 1.1

1.1     ! maekawa     1: /* mpfr_set_str_raw -- set a floating-point number from a binary string
        !             2:
        !             3: Copyright (C) 1999 PolKA project, Inria Lorraine and Loria
        !             4:
        !             5: This file is part of the MPFR Library.
        !             6:
        !             7: The MPFR Library is free software; you can redistribute it and/or modify
        !             8: it under the terms of the GNU Library General Public License as published by
        !             9: the Free Software Foundation; either version 2 of the License, or (at your
        !            10: option) any later version.
        !            11:
        !            12: The MPFR Library is distributed in the hope that it will be useful, but
        !            13: WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
        !            14: or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
        !            15: License for more details.
        !            16:
        !            17: You should have received a copy of the GNU Library General Public License
        !            18: along with the MPFR Library; see the file COPYING.LIB.  If not, write to
        !            19: the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
        !            20: MA 02111-1307, USA. */
        !            21:
        !            22: #include <stdio.h>
        !            23: #include <stdlib.h>
        !            24: #ifdef HAS_STRING_H
        !            25: #include <string.h>
        !            26: #else
        !            27: #include <strings.h>
        !            28: #endif
        !            29: #include "gmp.h"
        !            30: #include "gmp-impl.h"
        !            31: #include "longlong.h"
        !            32: #include "mpfr.h"
        !            33:
        !            34: /* Currently the number should be of the form +/- xxxx.xxxxxxEyy, with
        !            35:    decimal exponent. The mantissa of x is supposed to be large enough
        !            36:    to hold all the bits of str. */
        !            37:
        !            38: void
        !            39: #if __STDC__
        !            40: mpfr_set_str_raw(mpfr_ptr x, char *str)
        !            41: #else
        !            42: mpfr_set_str_raw(x, str)
        !            43:      mpfr_ptr x;
        !            44:      char *str;
        !            45: #endif
        !            46: {
        !            47:   char *str2, *str0, negative = 0;
        !            48:   unsigned long j, l, k = 0, xsize, cnt; mp_limb_t *xp;
        !            49:   long expn = 0, e; char *endstr2;
        !            50:
        !            51:   xp = x -> _mp_d;
        !            52:   xsize = 1 + (PREC(x)-1)/BITS_PER_MP_LIMB;
        !            53:   str0 = str2 = (char *) malloc((strlen(str)+1)*sizeof(char));
        !            54:
        !            55:   if (*str == '-') { negative = 1; str++; }
        !            56:   else if (*str == '+') str++;
        !            57:
        !            58:   while (*str == '0') { str++; }
        !            59:
        !            60:   while (*str == '0' || *str == '1')
        !            61:     { *(str2++) = *(str++); k++; }
        !            62:
        !            63:   if (*str == '.')
        !            64:     {
        !            65:       str++;
        !            66:       while (*str == '0' || *str == '1')
        !            67:        { *(str2++) = *(str++); }
        !            68:
        !            69:       if (*str == '[') { while (*str != ']') str++; }
        !            70:     }
        !            71:
        !            72:   if (*str == '[') { while (*str != ']') str++; }
        !            73:
        !            74:   if (*str == 'e' || *str == 'E')
        !            75:     {
        !            76:       e = atol(++str); /* signed exponent after 'e' or 'E' */
        !            77:       expn = k + e;
        !            78:       if (expn < e)
        !            79:          fprintf(stderr, "Warning: overflow in exponent in Str -> mpfr\n");
        !            80:     }
        !            81:   else expn=k;
        !            82:
        !            83:   endstr2 = str2;
        !            84:   *str2 = (char) 0; /* end of string */
        !            85:   l = (strlen(str0) - 1) / BITS_PER_MP_LIMB + 1; str2 = str0;
        !            86:
        !            87:   /* str2[0]..endstr2[-1] contains the mantissa */
        !            88:   for (k = 1; k <= l; k++)
        !            89:     {
        !            90:       j = 0;
        !            91:       xp[xsize - k] = 0;
        !            92:       while (str2<endstr2 && j < BITS_PER_MP_LIMB)
        !            93:        {
        !            94:          xp[xsize - k] = (xp[xsize - k] << 1) + (*str2 - '0');
        !            95:          str2++; j++;
        !            96:        }
        !            97:       xp[xsize - k] <<= (BITS_PER_MP_LIMB - j);
        !            98:     }
        !            99:
        !           100:   for (; k <= xsize; k++) { xp[xsize - k] = 0; }
        !           101:
        !           102:   count_leading_zeros(cnt, xp[xsize - 1]);
        !           103:   if (cnt) mpn_lshift(xp, xp, xsize, cnt);
        !           104:
        !           105:   x -> _mp_exp = expn - cnt;
        !           106:   x -> _mp_size = xsize; if (negative) CHANGE_SIGN(x);
        !           107:
        !           108:   free(str0);
        !           109:
        !           110:   /* May change to take into account : syntax errors, overflow in exponent,
        !           111:      string truncated because of size of x */
        !           112: }