You must have a 32 bit system then. Perhaps if you tell us what result you are getting and what result you were expecting, we can help you more.
Bill. On 23 November 2012 13:24, mgundes <mg...@hotmail.com> wrote: > > I changed but the result are same as previous, since both are in same size > in my system I guess. > > > On Fri, Nov 23, 2012 at 3:14 PM, Bill Hart <goodwillh...@googlemail.com> > wrote: >> >> One problem is that you are using unsigned int, instead of mp_limb_t >> (which is probably unsigned long or unsigned long long on your >> machine). >> >> Bill. >> >> On 23 November 2012 13:12, mgundes <mg...@hotmail.com> wrote: >> > >> > Hi Bill, thanks for reply. >> > >> > I run simple code below for different lengths of array >> > muıltiplication >> > and I got weird results with gmp_printf(). I also printed c array and it >> > seems true but printed result is weird. What is wrong or missing in >> > function >> > below? >> > >> > int main() { >> > >> > unsigned int a[4] = {100, 20, 30, 40}; >> > unsigned int b[4] = {200, 10, 5, 120}; >> > unsigned int c[8]; >> > >> > memset(c, 0, 8 * sizeof(unsigned int)); >> > mpn_mul((mp_limb_t *) c, >> > (mp_limb_t *) a, 1, >> > (mp_limb_t *) b, 1); >> > >> > for (int i=0; i<8; i++) >> > printf("c[%d]: %u\n", i, c[i]); >> > gmp_printf("\nresult: %Nu\n\n\n", c, 8); >> > >> > >> > memset(c, 0, 8 * sizeof(unsigned int)); >> > mpn_mul((mp_limb_t *) c, >> > (mp_limb_t *) a, 2, >> > (mp_limb_t *) b, 3); >> > >> > for (int i=0; i<8; i++) >> > printf("c[%d]: %u\n", i, c[i]); >> > gmp_printf("\nresult: %Nu\n\n\n", c, 8); >> > >> > memset(c, 0, 8 * sizeof(unsigned int)); >> > mpn_mul((mp_limb_t *) c, >> > (mp_limb_t *) a, 4, >> > (mp_limb_t *) b, 4); >> > >> > for (int i=0; i<8; i++) >> > printf("c[%d]: %u\n", i, c[i]); >> > gmp_printf("\nresult: %Nu\n\n\n", c, 8); >> > >> > >> > return 0; >> > } >> > >> > Kind Regards, >> > Thanks >> > >> > MahmutG >> > >> > >> > On Fri, Nov 23, 2012 at 3:09 AM, Bill Hart <goodwillh...@googlemail.com> >> > wrote: >> >> >> >> The result could be up to 8 limbs, which is why you should allocate 8 >> >> limbs for c. The top limb might turn out to be zero of course. >> >> >> >> The easiest way to print the result is to use gmp_printf with the %N >> >> option for mpn's. You need to also give it the number of limbs, as >> >> documented on pages 67-68 of our documentation. >> >> >> >> Bill. >> >> >> >> On 23 November 2012 00:55, mgundes <mg...@hotmail.com> wrote: >> >> > >> >> > Hi, >> >> > >> >> > I am not good at arithmetic but I need to calculate multiplication of >> >> > big >> >> > numbers. I will try to explain my need: >> >> > >> >> > For instance, if I have two 128 bit numbers represented with arrays >> >> > below: >> >> > >> >> > unsigned int a[4] = {100, 20, 30, 40}; >> >> > unsigned int b[4] = {200, 10, 5, 120}; >> >> > unsigned int c[4] = {0,0,0,0}; >> >> > >> >> > I want to multiply a and b, then assign the result to the c: >> >> > >> >> > mpn_mul_n((mp_limb_t *)c, (const mp_limb_t *)a, (const >> >> > mp_limb_t >> >> > *)b, >> >> > 4); >> >> > >> >> > Since mpn_mul takes result pointer as mp_limb_t type, then what if >> >> > result >> >> > exceeds? I mean the result of two integer multiplication probably >> >> > exceeds >> >> > integer size. Is there any example for multiplication of big numbers? >> >> > I >> >> > tried mpn_mul_n() as above and used mpn_get_str to see the result but >> >> > I >> >> > guess I could not use correctly. >> >> > >> >> > Kind regards, >> >> > Thanks >> >> > >> >> > -- >> >> > MahmutG >> >> > >> >> > -- >> >> > You received this message because you are subscribed to the Google >> >> > Groups >> >> > "mpir-devel" group. >> >> > To post to this group, send email to mpir-devel@googlegroups.com. >> >> > To unsubscribe from this group, send email to >> >> > mpir-devel+unsubscr...@googlegroups.com. >> >> > For more options, visit this group at >> >> > http://groups.google.com/group/mpir-devel?hl=en. >> >> >> >> -- >> >> You received this message because you are subscribed to the Google >> >> Groups >> >> "mpir-devel" group. >> >> To post to this group, send email to mpir-devel@googlegroups.com. >> >> To unsubscribe from this group, send email to >> >> mpir-devel+unsubscr...@googlegroups.com. >> >> For more options, visit this group at >> >> http://groups.google.com/group/mpir-devel?hl=en. >> >> >> > >> > >> > >> > -- >> > MahmutG >> > >> > -- >> > You received this message because you are subscribed to the Google >> > Groups >> > "mpir-devel" group. >> > To post to this group, send email to mpir-devel@googlegroups.com. >> > To unsubscribe from this group, send email to >> > mpir-devel+unsubscr...@googlegroups.com. >> > For more options, visit this group at >> > http://groups.google.com/group/mpir-devel?hl=en. >> >> -- >> You received this message because you are subscribed to the Google Groups >> "mpir-devel" group. >> To post to this group, send email to mpir-devel@googlegroups.com. >> To unsubscribe from this group, send email to >> mpir-devel+unsubscr...@googlegroups.com. >> For more options, visit this group at >> http://groups.google.com/group/mpir-devel?hl=en. >> > > > > -- > MahmutG > > -- > You received this message because you are subscribed to the Google Groups > "mpir-devel" group. > To post to this group, send email to mpir-devel@googlegroups.com. > To unsubscribe from this group, send email to > mpir-devel+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/mpir-devel?hl=en. -- You received this message because you are subscribed to the Google Groups "mpir-devel" group. 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