It seems that GMP provides only string serial开发者_StackOverflowization of the mpf (floating point) type:
mpf_get_str()
, mpf_class::get_str()
The mpz (integer) type has an additional interface for raw bytes: mpz_out_raw()
http://gmplib.org/manual/Function-Index.html
Am I missing something? Does anyone know of another library that can serialize GMP floats? Does anyone know of another bignum lib that offers robust serialization?
Edit: I'd be happy with serializing MPFR's mpfr_t, as well, which similarly only seems to offer string output: http://www.mpfr.org/mpfr-current/mpfr.html#Function-Index
This was a long time ago, but I wound up doing something like this:
int mpf_out_raw (FILE *f, mpf_t X) {
int expt; mpz_t Z; size_t nz;
expt = X->_mp_exp;
fwrite(&expt, sizeof(int), 1, f);
nz = X->_mp_size;
Z->_mp_alloc = nz;
Z->_mp_size = nz;
Z->_mp_d = X->_mp_d;
return (mpz_out_raw(f, Z) + sizeof(int));
}
void mpf_inp_raw (FILE *f, mpf_t X) {
int expt; mpz_t Z; size_t nz;
mpz_init (Z);
fread(&expt, sizeof(int), 1, f);
mpz_inp_raw (Z, f);
mpf_set_z (X, Z);
X->_mp_exp = expt;
mpz_clear (Z);
}
You can do input and output of the bytes in GMP floats. The manual page on I/O of Floats lists the following functions:
size_t mpf_out_str (FILE *stream, int base, size_t n_digits, mpf_t op)
size_t mpf_inp_str (mpf_t rop, FILE *stream, int base)
The confusing part about the manual is that it lists the I/O routines for the different types in different sections.
Edit: I was totally wrong! These functions are doing string conversion, not outputting the raw bytes.
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