3. Object Oriented Programming

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1 D Types 3. Obje Oriened Progrmming D ype. Se of vlues nd operions on hose vlues. Jv hs 8 primiive ypes.! Lnguge suppor for ommon operions: + - * / % &&!! boolen, hr,, bye, shor, long, flo, double D Type boolen double Se of Vlues rue, flse ny of 2 32 possible egers ny of 2 64 possible rels Buil-In Operions no, nd, or, xor dd, subr, muliply dd, subr, muliply We wn o wrie progrms h proess oher ypes of d.! s, piures, srings, inpu srems.! Complex numbers, mries, rionl numbers, polynomils,...! Pos, lines, rengles, irles, spheres,... Inroduion o Compuer Siene Rober Sedgewik nd Kevin Wyne Copyrigh 25 hp:// 2 Objes Consruors nd Mehods Obje. Holds d ype vlue; vrible nme refers o obje. Imp. Enbles us o ree our own d ypes; define operions on hem; nd egre o our progrms. To onsru new obje: Use keyword new nd nme of d ype. To pply n operion: Use nme of obje, he do operor, nd he nme of he mehod. D Type Sring 24 bis Se of Vlues sequene of hrers Operions ge red omponen, brighen Piure 2D rry of olors ge/se olor of pixel (i, j) lengh, subsring, ge ih hr Sring s = new Sring(""); N = s.lengh(); Sring = s.subsring(2, 4); 3 4

s 3.1. Using D Types. A sension in he eye from eleromgnei rdiion. Se of vlues (RGB represenion): 256 3 possible vlues, whih qunify he moun of red, green, nd blue, eh on sle of o.

2 s 3.1. Using D Types. A sension in he eye from eleromgnei rdiion. Se of vlues (RGB represenion): possible vlues, whih qunify he moun of red, green, nd blue, eh on sle of o. R G B Inroduion o Compuer Siene Rober Sedgewik nd Kevin Wyne Copyrigh 25 hp:// 6 s Using s in Jv. A sension in he eye from eleromgnei rdiion. One use of objes. Sore ggrege d in one vrible. Se of vlues (RGB represenion): possible vlues, whih qunify he moun of red, green, nd blue, eh on sle of o. Operions (pril): for vrible. Operion.geRed().geGreen().geBlue().brigher().drker().oSring() Desripion reurn red omponen reurn green omponen reurn blue omponen reurn brigher version of reurn drker version of reurn sring represenion of Reurn ype Sring Referene: hp://jv.sun.om/j2se/1.5./dos/pi/jv/w/.hml use impor o ess Jv librry impor jv.w.; publi lss Tes { publi si void min(sring[] rgs) { SdDrw.ree(6, 6); mgen = new (,, ); sienn = new (16, 82, 45); SdDrw.moveTo(.5,.5); SdDrw.se(mgen); SdDrw.spo(.667); SdDrw.se(sienn); SdDrw.spo(.5,.5); SdDrw.se(mgen); SdDrw.spo(.333); SdDrw.show(); 7 8

3 Monohrome Luminne OOP Conex for Monohrome luminne (Y). Effeive brighness of olor. Possible memory represenion. Appliion: Whih fon olors will be mos redble wih wh bkground olors on TV nd ompuer sreens? D D1 D2 D3 D4 D5 D6 15 D7 15 D8 15 NTSC formul: grysle =.2989r +.587g +.114b. publi si ogry( ) { r =.gered(); g =.gegreen(); b =.geblue(); luminne = () (.2989*r +.587*g +.114*b); gry = new (luminne, luminne, luminne); reurn gry; More uses. Pss olors o funions; reurn olors from funions. A B mgen gry D D6 ddress ddress Boom line: we re wriing progrms h mnipule olor. 9 1 Rser Grphis Imge Proessing: Monohrome Luminne (, ) j Rser grphis: bsis for imge proessing. Gol. Conver olor imge o grysle ording o NTSC formul. Se of vlues: 2D rry of objes (pixels). i impor jv.w.; Operions: for Piure vrible pi. Operion Desripion pi.geheigh() reurn heigh of imge pi.gewidh() reurn widh of imge pi.ge(i, j) reurn olor of pixel (i, j) pi.se(i, j, ) se olor of pixel (i, j) o pi.show() disply he piure in window pi.sve(s) sve he piure o file s Referene: hp:// Reurn ype void void void publi lss Grysle { publi si void min(sring rgs[]) { Piure pi1 = new Piure(rgs[]); widh = pi1.widh(); heigh = pi1.heigh(); Piure pi2 = new Piure(widh, heigh); for ( i = ; i < widh; i++) { for ( j = ; j < heigh; j++) { = pi.ge(i, j); gry = ogry(); pi2.se(i, j, gry); pi1.show(); pi2.show(); 11 12

Crees wo Piure objes nd windows. Swirl.jv.

13 14 Imge Proessing: Swirl Filer More Imge

Cree swirl speil effe by seing olor of oupu

(ii, jj). double i =.5 * widh; double j =.

( j = ; j < heigh; j++) { double di = i - i;

sin() + i); jj = ()( di*mh.sin() + dj*mh.

4 Imge Proessing: Monohrome Luminne Imge Proessing: Swirl Filer Grysle.jv. Crees wo Piure objes nd windows. Swirl.jv. Crees wo Piure objes nd windows Imge Proessing: Swirl Filer More Imge Proessing Effes Gol. Cree swirl speil effe by seing olor of oupu pixel (i, j) o olor of some oher inpu pixel (ii, jj). double i =.5 * widh; double j =.5 * heigh; for ( i = ; i < widh; i++) { for ( j = ; j < heigh; j++) { double di = i - i; double dj = j - j; double r = Mh.sqr(di*di +dj*dj); double = Mh.PI / 256 * r; ii = ()(-di*mh.os() + dj*mh.sin() + i); jj = ()( di*mh.sin() + dj*mh.os() + j); if (ii >= && ii < widh && jj >= && jj < heigh) pi2.se(i, j, pi1.ge(ii, jj)); RGB olor seprion Wve 15 Glss Sobel Edge Deeion 16

5 OOP Conex for Piure Srings Immubiliy. Cn' hnge obje's vlue one reed. Mubiliy. Cn hnge Piure obje's vlue. Sring d ype: bsis for ex proessing. Se of vlues: sequene of Uniode hrers. Operions (pril): for Sring vrible s. = pi.ge(, ); pi.se(3,, ); D D4 D8 Operion s.lengh() s.hra(1) Desripion reurn lengh of s reurn hr of s index 1 s Reurn 5 e DC s.subsring(1, 4) reurn subsring of s from 1 (inlusive) o 4 (exlusive) ell s.ouppercse() reurn upperse version of s HELLO Obje referene is nlogous o vrible nme. s.endswih(".om") does s end wih.om? nn.om rue! We n mnipule he vlue h i holds.! We n pss i o funion / mehod. s.ompreto("bye") reurn posiive eger, negive eger or zero bsed on sring omprison -1 Referene: hp://jv.sun.om/j2se/1.5./dos/pi/jv/lng/sring.hml Soring Srings Redundny Deeor Anlysis of lgorihms leure: quiksor rry of rel numbers. To sor srings:! Reple ll ourrenes of double wih Sring. Longes repeed subsring. Given sring, find he longes subsring h ppers les wie. g g si void exh(sring[], i, j) { Sring swp = [i]; [i] = [j]; [j] = swp;! Rewrie less o ompre elemens lexiogrphilly. Brue fore.! Try ll indies i nd j for sr of possible mh.! Compue longes ommon prefix for eh pir (qudri). g g i j si boolen less(sring s, Sring ) { reurn (s.ompreto() < ); Appliions.! Compuionl moleulr biology.! Burrows-Wheeler rnsform for d ompression. 19 2

6 Longes Repeed Subsring: A Soring Soluion Longes Repeed Subsring: Jv Implemenion A soring soluion.! Form suffixes, nd sor hem o bring repeed subsrings ogeher.! Compue longes prefix beween N-1 djen suffixes. g g g g g g g g g g g g g g g g g g g g g g g g g g g g g g g g g g g g g g g g Suffix soring implemenion. N = s.lengh(); Sring[] suffixes = new Sring[N]; for ( i = ; i < N; i++) suffixes[i] = s.subsring(i, N); Arrys.sor(suffixes); Longes repeed subsring. Serh only djen suffixes. Sring lrs = ""; for ( i = ; i < N-1; i++) { Sring x = lp(suffixes[i], suffixes[i+1]); if (x.lengh() > lrs.lengh()) lrs = x; LCP. Find he longes sring h is prefix of boh s nd. Ex: lp("g", "g") = "g" OOP Conex for Srings Longes Repeed Subsring: Anlysis Possible memory represenion of sring.! s = "gg"; Compuionl experimens. D D1 D2 D3 D4 D5 g D6 D7 D8 D9 DA DB DC DD g DE s A D A1 15 Inpu File LRS.jv Amendmens Chrers 2,162 18,369 Brue.6 se 37 se Suffix Sor.14 se.25 se Lengh ddress lengh Aesop's Fbles 191, se 1. se 58! = s.subsring(5, 15); B D5 B1 1 Moby Dik Bible 1.2 million 4. million 43 hours 2 dys 7.6 se 34 se Chromosome million 2 monhs 61 se 12,567! No hrers re opied when you invoke subsring mehod! Pi 1 million 4 monhs 84 se 14 Consequenes.! Clling subsring kes onsn ime (insed of liner).! Creing suffixes kes liner spe (insed of qudri). esimed Lesson. Soring o he resue; enbles new reserh

7 Non-Sndrd Inpu Sreen Srping Sndrd inpu: from keybord, or use OS o redire from one file. Gol: red from severl differen inpu srems. In d ype. Red ex from sdin, file, web sie, or nework. Ex: Are wo ex files idenil? publi lss Diff { publi si void min(sring[] rgs) { In in = new In(rgs[]); In in1 = new In(rgs[1]); Sring s = in.redall(); Sring = in1.redall(); Sysem.ou.prln(s.equls()); Find urren sok prie of Google.! s.indexof(, i): index of 1 s ourrene of pern in sring s, sring offse i.! Red rw hml from hp://finne.yhoo.om/q?s=goog NYSE symbol! Find 1 s sring delimied by <b> nd </b> ppering fer Ls Trde publi lss SokQuoe { publi si void min(sring[] rgs) { Sring nme = "hp://finne.yhoo.om/q?s=" + rgs[]; In in = new In(nme); Sring inpu = in.redall(); sr = inpu.indexof("ls Trde:", ); from = inpu.indexof("<b>", sr); o = inpu.indexof("</b>", from); Sring prie = inpu.subsring(from + 3, o); Sysem.ou.prln(prie); % jv SokQuoe goog Dy Trder OOP Summry Add bells nd whisles.! Plo prie in rel-ime.! Noify user if prie dips below erin prie.! Embed logi o deermine when o buy nd sell.! Auomilly send buy nd sell orders o rding firm. Obje. Holds d ype vlue; vrible nme refers o obje. In Jv, progrms mnipule referenes o objes.! Exepion: primiive ypes, e.g., boolen,, double.! Referene ypes: Sring, Piure,, rrys, everyhing else.! OOP puris: lnguge should no hve sepre primiive ypes. Wrning. Use your own finnil risk. Boom line. We wroe progrms h mnipule olors, piures, srings, nd inpu srems. Nex ime. We'll lern how o ree new d ypes so h we n wrie progrms o mnipule our own bsrions

two values, false and true used in mathematical logic, and to two voltage levels, LOW and HIGH used in switching circuits.

two values, false and true used in mathematical logic, and to two voltage levels, LOW and HIGH used in switching circuits. Digil Logi/Design. L. 3 Mrh 2, 26 3 Logi Ges nd Boolen Alger 3. CMOS Tehnology Digil devises re predominnly mnufured in he Complemenry-Mel-Oide-Semionduor (CMOS) ehnology. Two ypes of swihes, s disussed