📄 random.3
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2655(a)S2741(single)S3022(word.)S3320(\(Two)S3580(other)S3828(routines)S4193(are)S4358(provided)S4756(to)S4874(deal)S5082(with)S3552 V1080(restarting/changing)S(random)307 1887 A2224(number)S2561(generators\).)S3095(Like)S10 B3310(rand)S10 R3517(\(3\),)S3690(however,)S10 B4092(random)S10 R(will)157 4463 A4651(by)S4782(default)S5093(pro-)S3672 V1080(duce)S1295(a)S1365(sequence)S1759(of)S1868(numbers)S2239(that)S2415(can)S2580(be)S(duplicated)419 2700 A3144(by)S(calling)274 3269 A10 B3568(srandom)S10 R3973(with)S10 B4177(1)S10 R4252(as)S4361(the)S4509(seed.)S3840 V1080(The)S10 B1262(initstate)S10 R1635(routine)S1945(allows)S2233(a)S2303(state)S2513(array,)S2771(passed)S3064(in)S3167(as)S3277(an)S3398(argument,)S3829(to)S3933(be)S(initialized)403 4054 A4483(for)S4627(future)S4894(use.)S5104(The)S3960 V1080(size)S1265(of)S1377(the)S1528(state)S1741(array)S1976(\(in)S2115(bytes\))S2388(is)S2482(used)S2693(by)S10 B2820(initstate)S10 R3195(to)S3300(decide)S3590(how)S(sophisticated)525 3790 A4342(a)S(random)307 4414 A4748(number)S5082(gen-)S4080 V1080(erator)S1343(it)S(should)267 1426 A1720(use)S1881(--)S1976(the)S2126(more)S2360(state,)S2597(the)S2747(better)S3004(the)S(random)307 3154 A3488(numbers)S(will)157 3861 A4045(be.)S4217(\(Current)S4587("optimal")S5004(values)S4200 V1080(for)S1232(the)S(amount)301 1389 A1724(of)S1842(state)S2061(information)S2570(are)S2728(8,)S2837(32,)S2996(64,)S(128,)175 3155 A3364(and)S(256)150 3543 A3727(bytes;)S4001(other)S(amounts)340 4241 A(will)157 4614 A4804(be)S(rounded)329 4932 A4320 V1080(down)S1331(to)S1437(the)S1588(nearest)S(known)273 1902 A(amount.)326 2204 A2584(Using)S2853(less)S3033(than)S3235(8)S3314(bytes)S(will)157 3555 A3741(cause)S3994(an)S4118(error\).)S4428(The)S4614(seed)S4822(for)S4969(the)S5121(ini-)S4440 V1080(tialization)S1509(\(which)S1815(speci\256es)S2188(a)S2259(starting)S2587(point)S2819(for)S2963(the)S(random)307 3112 A3445(number)S3777(sequence,)S4196(and)S4366(provides)S4737(for)S4880(restarting)S4560 V1080(at)S1191(the)S1352(same)S1597(point\))S1875(is)S1980(also)S2180(an)S2313(argument.)S10 B2781(Initstate)S10 R3178(returns)S3496(a)S3579(pointer)S3902(to)S4018(the)S4179(previous)S4563(state)S4786(information)S4680 V1080(array.)S4848 V1080(Once)S1320(a)S1392(state)S1604(has)S1766(been)S(initialized,)428 1984 A2440(the)S10 B2591(setstate)S10 R2939(routine)S3252(provides)S3626(for)S3772(rapid)S4007(switching)S4426(between)S4790(states.)S10 B5092(Set-)S4968 V1080(state)S10 R1317(returns)S1632(a)S1712(pointer)S2032(to)S2144(the)S2301(previous)S2681(state)S2900(array;)S3170(its)S3299(argument)S3713(state)S3932(array)S4174(is)S4275(used)S4493(for)S4645(further)S(random)307 4954 A5088 V1080(number)S1412(generation)S(until)184 1862 A2071(the)S2219(next)S2417(call)S2588(to)S10 B2691(initstate)S10 R3064(or)S10 B3173(setstate)S10 R3493(.)S5256 V1080(Once)S1319(a)S1390(state)S1601(array)S1835(has)S1996(been)S(initialized,)428 2213 A2668(it)S2751(may)S2951(be)S3073(restarted)S3448(at)S3548(a)S3620(different)S3995(point)S4228(either)S4485(by)S(calling)274 4612 A10 B4913(initstate)S5376 V10 R1080(\(with)S1321(the)S1471(desired)S1789(seed,)S2020(the)S2170(state)S2382(array,)S2642(and)S2814(its)S2936(size\))S3154(or)S3265(by)S(calling)274 3392 A3693(both)S10 B3898(setstate)S10 R4245(\(with)S4485(the)S4635(state)S4847(array\))S5116(and)S5496 V10 B1080(srandom)S10 R1489(\(with)S1731(the)S1883(desired)S2203(seed\).)S2495(The)S2681(advantage)S3118(of)S(calling)274 3231 A3534(both)S10 B3741(setstate)S10 R4090(and)S10 B4264(srandom)S10 R4673(is)S4770(that)S4951(the)S5104(size)S5616 V1080(of)S1189(the)S1337(state)S1547(array)S1780(does)S1989(not)S2142(have)S2357(to)S2460(be)S2580(remembered)S3109(after)S3320(it)S3401(is)S(initialized.)428 3493 A5784 V1080(With)S(256)150 1318 A1505(bytes)S1754(of)S1875(state)S2097(information,)S2634(the)S2794(period)S3089(of)S3211(the)S(random)307 3372 A3717(number)S4062(generator)S4481(is)S4586(greater)S4905(than)S5116(2)S5734 V7 R5166(69)S5784 V10 R5236(,)S5904 V1080(which)S(should)267 1351 A1643(be)S1763(suf\256cient)S2163(for)S2306(most)S2526(purposes.)S6072 V9 R720(A)S722(AU)S790(UT)S858(TH)S916(HO)S984(OR)S1052(R)S6192 V10 R1080(Earl)S1274(T.)S1386(Cohen)S6360 V9 R720(D)S722(DI)S790(IA)S823(AG)S891(GN)S959(NO)S1027(OS)S1095(ST)S1147(TI)S1205(IC)S1238(CS)S1300(S)S6480 V10 R1080(If)S10 B1173(initstate)S10 R1546(is)S1638(called)S1904(with)S2108(less)S2284(than)S2483(8)S2559(bytes)S2797(of)S2907(state)S3118(information,)S3644(or)S3754(if)S10 B3842(setstate)S10 R4188(detects)S4494(that)S4671(the)S4820(state)S5031(infor-)S6600 V1080(mation)S1384(has)S1543(been)S1758(garbled,)S2110(error)S2332(messages)S2737(are)S2886(printed)S3196(on)S3321(the)S3469(standard)S3835(error)S4057(output.)S6768 V9 R720(S)S722(SE)S774(EE)S832(E)S913(A)S915(AL)S983(LS)S1041(SO)S1093(O)S6888 V10 B1080(rand)S10 R1287(\(3\).)S7056 V9 R720(N)S722(NO)S790(OT)S858(TE)S916(ES)S974(S)S7176 V10 B1080(initstate)S10 R1466(and)S10 B1650(setstate)S10 R2009(are)S2172(not)S2339(declared)S2720(in)S10 I2837(<stdlib.h>)S10 R3279(,)S3343(programmers)S3919(must)S4153(provide)S4499(their)S4723(own)S4935(declara-)S7296 V1080(tions.)S7903 V720(Page)S941(1)S2545(\()S2587(September)S3043(29,)S(1985)200 3193 A3401(\))S4455(September)S4911(13,)S(1996)200 5061 A8143 VEP%%Page: 2 2BP/slant 0 def/height 0 def480 V10 R(RANDOM)448 720 A1176(\()S1218(3)S1276(\))S2696(Eighth)S(Edition)296 2989 A(RANDOM)448 4671 A5127(\()S5169(3)S5227(\))S960 V9 R720(B)S722(BU)S784(UG)S852(GS)S920(S)S1080 V10 R(About)251 1080 A1356(2/3)S1509(the)S1657(speed)S1911(of)S10 B2020(rand)S10 R2227(\(3\).)S7903 V720(September)S1176(13,)S(1996)200 1326 A2545(\()S2587(September)S3043(29,)S(1985)200 3193 A3401(\))S4990(Page)S5211(2)S8143 VEP%%Trailer%%DocumentFonts: Times-Roman Times-Bold Times-Italic Symbol%%Pages: 2⌨️ 快捷键说明
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