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Logical and Bit Manipulation Functions

These functions behave as if twos complement arithmetic were used (although sign-magnitude is the actual implementation). The least significant bit is number 0.

void mpz_and (mpz_t rop, mpz_t op1, mpz_t op2)

Function

Set rop to op1 logical-and op2.

void mpz_ior (mpz_t rop, mpz_t op1, mpz_t op2)

Function

Set rop to op1 inclusive-or op2.

void mpz_xor (mpz_t rop, mpz_t op1, mpz_t op2)

Function

Set rop to op1 exclusive-or op2.

void mpz_com (mpz_t rop, mpz_t op)

Function

Set rop to the one's complement of op.

unsigned long int mpz_popcount (mpz_t op)

Function

If op>=0, return the population count of op, which is the number of 1 bits in the binary representation. If op<0, the number of 1s is infinite, and the return value is MAX_ULONG, the largest possible unsigned long.

unsigned long int mpz_hamdist (mpz_t op1, mpz_t op2)

Function

If op1 and op2 are both >=0 or both <0, return the hamming distance between the two operands, which is the number of bit positions where op1 and op2 have different bit values. If one operand is >=0 and the other <0 then the number of bits different is infinite, and the return value is MAX_ULONG, the largest possible unsigned long.

unsigned long int mpz_scan0 (mpz_t op, unsigned long int starting_bit)	Function
unsigned long int mpz_scan1 (mpz_t op, unsigned long int starting_bit)	Function

Scan op, starting from bit starting_bit, towards more significant bits, until the first 0 or 1 bit (respectively) is found. Return the index of the found bit. If the bit at starting_bit is already what's sought, then starting_bit is returned. If there's no bit found, then MAX_ULONG is returned. This will happen in mpz_scan0 past the end of a positive number, or mpz_scan1 past the end of a negative.

void mpz_setbit (mpz_t rop, unsigned long int bit_index)

Function

Set bit bit_index in rop.

void mpz_clrbit (mpz_t rop, unsigned long int bit_index)

Function

Clear bit bit_index in rop.

int mpz_tstbit (mpz_t op, unsigned long int bit_index)

Function

Test bit bit_index in op and return 0 or 1 accordingly.