Thanks, online calculator is very good.
On Fri, Nov 23, 2012 at 4:19 PM, Bill Hart <goodwillh...@googlemail.com>wrote: > I Googled "online bignum calculator" and this popped up: > > https://defuse.ca/big-number-calculator.htm > > Python is fine of course. > > Bill. > > On 23 November 2012 13:59, mgundes <mg...@hotmail.com> wrote: > > > > By the way I use python for not too big number verification. > > Is there any application or web site to easily verify big number > > multiplications? > > > > > > On Fri, Nov 23, 2012 at 3:51 PM, mgundes <mg...@hotmail.com> wrote: > >> > >> > >> Opps, sorry Bill, I have miscalculated the expected result, I > checked > >> again and found my mistake. Thank for your concern. > >> > >> Regards > >> > >> > >> > >> On Fri, Nov 23, 2012 at 3:26 PM, Bill Hart <goodwillh...@googlemail.com > > > >> wrote: > >>> > >>> 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. > >>> 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 > > > > > > > > > > -- > > 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. 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