Convert op to a
double, truncating if necessary (i.e. rounding
If the exponent from the conversion is too big or too small to fit a
double then the result is system dependent. For too big an infinity is
returned when available. For too small 0.0 is normally returned.
Hardware overflow, underflow and denorm traps may or may not occur.
Set rop to the value of op. There is no rounding, this conversion is exact.
Convert op to a string of digits in base base. The base argument may vary from 2 to 62 or from -2 to -36. The string will be of the form ‘num/den’, or if the denominator is 1 then just ‘num’.
For base in the range 2..36, digits and lower-case letters are used; for -2..-36, digits and upper-case letters are used; for 37..62, digits, upper-case letters, and lower-case letters (in that significance order) are used.
If str is
NULL, the result string is allocated using the current
allocation function (see Custom Allocation). The block will be
strlen(str)+1 bytes, that being exactly enough for the string and
If str is not
NULL, it should point to a block of storage large
enough for the result, that being
mpz_sizeinbase (mpq_numref(op), base) + mpz_sizeinbase (mpq_denref(op), base) + 3
The three extra bytes are for a possible minus sign, possible slash, and the null-terminator.
A pointer to the result string is returned, being either the allocated block, or the given str.