[ Numaibine @ 11.09.2007. 14:45 ] @
| Evo ovako, pokusavam vec neko vreme da pronadjem logiku u ovoj postavci: Imamo matricu: 3.1 | 2.3 | 1.4 5.0 | 1.1 | Zadate su i definicije: cnt: an array of length number of columns; the jth entry specifies the number of non-zeros in the jth column. beg: an array of length number of columns; the jth entry specifies the location of the start of the entries for the jth column in the arrays "ind" and "val". ind: an array that contains the row indices of the non-zero entries in the matrix. The indices of the jth column must be stored consecutively starting at entry number beg[j] (there are cnt[j] entries for the jth column). val: an array that contains the values of the non-zero entries in the matrix. The non-zero values of the jth column must be stored consecutively starting at entry number beg[j] (there are cnt[j] entries for the jth column). Data su i resenja: cnt[3] = { 2, 2, 1 } beg[3] = { 0, 2, 4 } ind[5] = { 0, 1, 0, 1, 0 } val[5] = { 3.1, 5.0, 2.3, 1.1, 1.4 } E, sad za niz "cnt" razumem: postoje tri kolone, pa samim tim i 3 clana niza. Clanovi niza predstavljaju brojeve ne nultih vrednosti u kolonama, dakle u prvoj koloni imamo dve ne nulte vrednosti, u drugoj takodje i u trecoj jednu. (2,2,1) Takodje razumem i niz "val": sam niz predstavljaju vrednosti matrice, dakle: 3.1, 5.0, 2.3, 1.1, 1.4 Ono sto ne razumem jeste kako se doslo do resenja za nizove "beg" i "ind"??? Evo jos jedan primer, ali sa drugim vrednostima, pa ukoliko neko vidi vezu izmedju ova dva primera i otkrije sta predstavljaju nizovi "beg" i "ind" zamolio bih ga da postuje odgovor. Hvala unapred! 3.5 | 2.1 ___ | 3.0 cnt[2] = { 1, 2 } beg[2] = { 0, 1 } ind[3] = { 0, 0, 1 } val[3] = { 3.5, 2.1, 3.0 } |