675 lines
26 KiB
Python
675 lines
26 KiB
Python
# util.py
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# -------
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# Licensing Information: You are free to use or extend these projects for
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# educational purposes provided that (1) you do not distribute or publish
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# solutions, (2) you retain this notice, and (3) you provide clear
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# attribution to UC Berkeley, including a link to http://ai.berkeley.edu.
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#
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# Attribution Information: The Pacman AI projects were developed at UC Berkeley.
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# The core projects and autograders were primarily created by John DeNero
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# (denero@cs.berkeley.edu) and Dan Klein (klein@cs.berkeley.edu).
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# Student side autograding was added by Brad Miller, Nick Hay, and
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# Pieter Abbeel (pabbeel@cs.berkeley.edu).
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# util.py
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# -------
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# Licensing Information: You are free to use or extend these projects for
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# educational purposes provided that (1) you do not distribute or publish
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# solutions, (2) you retain this notice, and (3) you provide clear
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# attribution to UC Berkeley, including a link to http://ai.berkeley.edu.
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#
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# Attribution Information: The Pacman AI projects were developed at UC Berkeley.
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# The core projects and autograders were primarily created by John DeNero
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# (denero@cs.berkeley.edu) and Dan Klein (klein@cs.berkeley.edu).
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# Student side autograding was added by Brad Miller, Nick Hay, and
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# Pieter Abbeel (pabbeel@cs.berkeley.edu).
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import sys
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import inspect
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import heapq, random
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import cStringIO
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class FixedRandom:
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def __init__(self):
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fixedState = (3, (2147483648L, 507801126L, 683453281L, 310439348L, 2597246090L, \
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2209084787L, 2267831527L, 979920060L, 3098657677L, 37650879L, 807947081L, 3974896263L, \
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881243242L, 3100634921L, 1334775171L, 3965168385L, 746264660L, 4074750168L, 500078808L, \
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776561771L, 702988163L, 1636311725L, 2559226045L, 157578202L, 2498342920L, 2794591496L, \
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4130598723L, 496985844L, 2944563015L, 3731321600L, 3514814613L, 3362575829L, 3038768745L, \
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2206497038L, 1108748846L, 1317460727L, 3134077628L, 988312410L, 1674063516L, 746456451L, \
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3958482413L, 1857117812L, 708750586L, 1583423339L, 3466495450L, 1536929345L, 1137240525L, \
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3875025632L, 2466137587L, 1235845595L, 4214575620L, 3792516855L, 657994358L, 1241843248L, \
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1695651859L, 3678946666L, 1929922113L, 2351044952L, 2317810202L, 2039319015L, 460787996L, \
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3654096216L, 4068721415L, 1814163703L, 2904112444L, 1386111013L, 574629867L, 2654529343L, \
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3833135042L, 2725328455L, 552431551L, 4006991378L, 1331562057L, 3710134542L, 303171486L, \
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1203231078L, 2670768975L, 54570816L, 2679609001L, 578983064L, 1271454725L, 3230871056L, \
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2496832891L, 2944938195L, 1608828728L, 367886575L, 2544708204L, 103775539L, 1912402393L, \
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1098482180L, 2738577070L, 3091646463L, 1505274463L, 2079416566L, 659100352L, 839995305L, \
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1696257633L, 274389836L, 3973303017L, 671127655L, 1061109122L, 517486945L, 1379749962L, \
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3421383928L, 3116950429L, 2165882425L, 2346928266L, 2892678711L, 2936066049L, 1316407868L, \
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2873411858L, 4279682888L, 2744351923L, 3290373816L, 1014377279L, 955200944L, 4220990860L, \
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2386098930L, 1772997650L, 3757346974L, 1621616438L, 2877097197L, 442116595L, 2010480266L, \
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2867861469L, 2955352695L, 605335967L, 2222936009L, 2067554933L, 4129906358L, 1519608541L, \
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1195006590L, 1942991038L, 2736562236L, 279162408L, 1415982909L, 4099901426L, 1732201505L, \
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2934657937L, 860563237L, 2479235483L, 3081651097L, 2244720867L, 3112631622L, 1636991639L, \
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3860393305L, 2312061927L, 48780114L, 1149090394L, 2643246550L, 1764050647L, 3836789087L, \
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3474859076L, 4237194338L, 1735191073L, 2150369208L, 92164394L, 756974036L, 2314453957L, \
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323969533L, 4267621035L, 283649842L, 810004843L, 727855536L, 1757827251L, 3334960421L, \
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3261035106L, 38417393L, 2660980472L, 1256633965L, 2184045390L, 811213141L, 2857482069L, \
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2237770878L, 3891003138L, 2787806886L, 2435192790L, 2249324662L, 3507764896L, 995388363L, \
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856944153L, 619213904L, 3233967826L, 3703465555L, 3286531781L, 3863193356L, 2992340714L, \
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413696855L, 3865185632L, 1704163171L, 3043634452L, 2225424707L, 2199018022L, 3506117517L, \
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3311559776L, 3374443561L, 1207829628L, 668793165L, 1822020716L, 2082656160L, 1160606415L, \
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3034757648L, 741703672L, 3094328738L, 459332691L, 2702383376L, 1610239915L, 4162939394L, \
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557861574L, 3805706338L, 3832520705L, 1248934879L, 3250424034L, 892335058L, 74323433L, \
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3209751608L, 3213220797L, 3444035873L, 3743886725L, 1783837251L, 610968664L, 580745246L, \
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4041979504L, 201684874L, 2673219253L, 1377283008L, 3497299167L, 2344209394L, 2304982920L, \
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3081403782L, 2599256854L, 3184475235L, 3373055826L, 695186388L, 2423332338L, 222864327L, \
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1258227992L, 3627871647L, 3487724980L, 4027953808L, 3053320360L, 533627073L, 3026232514L, \
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2340271949L, 867277230L, 868513116L, 2158535651L, 2487822909L, 3428235761L, 3067196046L, \
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3435119657L, 1908441839L, 788668797L, 3367703138L, 3317763187L, 908264443L, 2252100381L, \
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764223334L, 4127108988L, 384641349L, 3377374722L, 1263833251L, 1958694944L, 3847832657L, \
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1253909612L, 1096494446L, 555725445L, 2277045895L, 3340096504L, 1383318686L, 4234428127L, \
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1072582179L, 94169494L, 1064509968L, 2681151917L, 2681864920L, 734708852L, 1338914021L, \
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1270409500L, 1789469116L, 4191988204L, 1716329784L, 2213764829L, 3712538840L, 919910444L, \
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1318414447L, 3383806712L, 3054941722L, 3378649942L, 1205735655L, 1268136494L, 2214009444L, \
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2532395133L, 3232230447L, 230294038L, 342599089L, 772808141L, 4096882234L, 3146662953L, \
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2784264306L, 1860954704L, 2675279609L, 2984212876L, 2466966981L, 2627986059L, 2985545332L, \
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2578042598L, 1458940786L, 2944243755L, 3959506256L, 1509151382L, 325761900L, 942251521L, \
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4184289782L, 2756231555L, 3297811774L, 1169708099L, 3280524138L, 3805245319L, 3227360276L, \
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3199632491L, 2235795585L, 2865407118L, 36763651L, 2441503575L, 3314890374L, 1755526087L, \
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17915536L, 1196948233L, 949343045L, 3815841867L, 489007833L, 2654997597L, 2834744136L, \
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417688687L, 2843220846L, 85621843L, 747339336L, 2043645709L, 3520444394L, 1825470818L, \
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647778910L, 275904777L, 1249389189L, 3640887431L, 4200779599L, 323384601L, 3446088641L, \
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4049835786L, 1718989062L, 3563787136L, 44099190L, 3281263107L, 22910812L, 1826109246L, \
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745118154L, 3392171319L, 1571490704L, 354891067L, 815955642L, 1453450421L, 940015623L, \
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796817754L, 1260148619L, 3898237757L, 176670141L, 1870249326L, 3317738680L, 448918002L, \
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4059166594L, 2003827551L, 987091377L, 224855998L, 3520570137L, 789522610L, 2604445123L, \
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454472869L, 475688926L, 2990723466L, 523362238L, 3897608102L, 806637149L, 2642229586L, \
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2928614432L, 1564415411L, 1691381054L, 3816907227L, 4082581003L, 1895544448L, 3728217394L, \
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3214813157L, 4054301607L, 1882632454L, 2873728645L, 3694943071L, 1297991732L, 2101682438L, \
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3952579552L, 678650400L, 1391722293L, 478833748L, 2976468591L, 158586606L, 2576499787L, \
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662690848L, 3799889765L, 3328894692L, 2474578497L, 2383901391L, 1718193504L, 3003184595L, \
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3630561213L, 1929441113L, 3848238627L, 1594310094L, 3040359840L, 3051803867L, 2462788790L, \
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954409915L, 802581771L, 681703307L, 545982392L, 2738993819L, 8025358L, 2827719383L, \
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770471093L, 3484895980L, 3111306320L, 3900000891L, 2116916652L, 397746721L, 2087689510L, \
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721433935L, 1396088885L, 2751612384L, 1998988613L, 2135074843L, 2521131298L, 707009172L, \
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2398321482L, 688041159L, 2264560137L, 482388305L, 207864885L, 3735036991L, 3490348331L, \
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1963642811L, 3260224305L, 3493564223L, 1939428454L, 1128799656L, 1366012432L, 2858822447L, \
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1428147157L, 2261125391L, 1611208390L, 1134826333L, 2374102525L, 3833625209L, 2266397263L, \
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3189115077L, 770080230L, 2674657172L, 4280146640L, 3604531615L, 4235071805L, 3436987249L, \
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509704467L, 2582695198L, 4256268040L, 3391197562L, 1460642842L, 1617931012L, 457825497L, \
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1031452907L, 1330422862L, 4125947620L, 2280712485L, 431892090L, 2387410588L, 2061126784L, \
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896457479L, 3480499461L, 2488196663L, 4021103792L, 1877063114L, 2744470201L, 1046140599L, \
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2129952955L, 3583049218L, 4217723693L, 2720341743L, 820661843L, 1079873609L, 3360954200L, \
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3652304997L, 3335838575L, 2178810636L, 1908053374L, 4026721976L, 1793145418L, 476541615L, \
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|
973420250L, 515553040L, 919292001L, 2601786155L, 1685119450L, 3030170809L, 1590676150L, \
|
|
1665099167L, 651151584L, 2077190587L, 957892642L, 646336572L, 2743719258L, 866169074L, \
|
|
851118829L, 4225766285L, 963748226L, 799549420L, 1955032629L, 799460000L, 2425744063L, \
|
|
2441291571L, 1928963772L, 528930629L, 2591962884L, 3495142819L, 1896021824L, 901320159L, \
|
|
3181820243L, 843061941L, 3338628510L, 3782438992L, 9515330L, 1705797226L, 953535929L, \
|
|
764833876L, 3202464965L, 2970244591L, 519154982L, 3390617541L, 566616744L, 3438031503L, \
|
|
1853838297L, 170608755L, 1393728434L, 676900116L, 3184965776L, 1843100290L, 78995357L, \
|
|
2227939888L, 3460264600L, 1745705055L, 1474086965L, 572796246L, 4081303004L, 882828851L, \
|
|
1295445825L, 137639900L, 3304579600L, 2722437017L, 4093422709L, 273203373L, 2666507854L, \
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|
3998836510L, 493829981L, 1623949669L, 3482036755L, 3390023939L, 833233937L, 1639668730L, \
|
|
1499455075L, 249728260L, 1210694006L, 3836497489L, 1551488720L, 3253074267L, 3388238003L, \
|
|
2372035079L, 3945715164L, 2029501215L, 3362012634L, 2007375355L, 4074709820L, 631485888L, \
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|
3135015769L, 4273087084L, 3648076204L, 2739943601L, 1374020358L, 1760722448L, 3773939706L, \
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|
1313027823L, 1895251226L, 4224465911L, 421382535L, 1141067370L, 3660034846L, 3393185650L, \
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|
1850995280L, 1451917312L, 3841455409L, 3926840308L, 1397397252L, 2572864479L, 2500171350L, \
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|
3119920613L, 531400869L, 1626487579L, 1099320497L, 407414753L, 2438623324L, 99073255L, \
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3175491512L, 656431560L, 1153671785L, 236307875L, 2824738046L, 2320621382L, 892174056L, \
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230984053L, 719791226L, 2718891946L, 624L), None)
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self.random = random.Random()
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self.random.setstate(fixedState)
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"""
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Data structures useful for implementing SearchAgents
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"""
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class Stack:
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"A container with a last-in-first-out (LIFO) queuing policy."
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def __init__(self):
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self.list = []
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def push(self,item):
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"Push 'item' onto the stack"
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self.list.append(item)
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def pop(self):
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"Pop the most recently pushed item from the stack"
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return self.list.pop()
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def isEmpty(self):
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"Returns true if the stack is empty"
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return len(self.list) == 0
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class Queue:
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"A container with a first-in-first-out (FIFO) queuing policy."
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def __init__(self):
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self.list = []
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def push(self,item):
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"Enqueue the 'item' into the queue"
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self.list.insert(0,item)
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def pop(self):
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"""
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Dequeue the earliest enqueued item still in the queue. This
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operation removes the item from the queue.
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"""
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return self.list.pop()
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def isEmpty(self):
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"Returns true if the queue is empty"
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return len(self.list) == 0
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class PriorityQueue:
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"""
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Implements a priority queue data structure. Each inserted item
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has a priority associated with it and the client is usually interested
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in quick retrieval of the lowest-priority item in the queue. This
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data structure allows O(1) access to the lowest-priority item.
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"""
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def __init__(self):
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self.heap = []
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self.count = 0
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def push(self, item, priority):
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entry = (priority, self.count, item)
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heapq.heappush(self.heap, entry)
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self.count += 1
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def pop(self):
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(_, _, item) = heapq.heappop(self.heap)
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return item
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def isEmpty(self):
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return len(self.heap) == 0
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def update(self, item, priority):
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# If item already in priority queue with higher priority, update its priority and rebuild the heap.
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# If item already in priority queue with equal or lower priority, do nothing.
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# If item not in priority queue, do the same thing as self.push.
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for index, (p, c, i) in enumerate(self.heap):
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if i == item:
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if p <= priority:
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break
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del self.heap[index]
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self.heap.append((priority, c, item))
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heapq.heapify(self.heap)
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break
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else:
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self.push(item, priority)
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class PriorityQueueWithFunction(PriorityQueue):
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"""
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Implements a priority queue with the same push/pop signature of the
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Queue and the Stack classes. This is designed for drop-in replacement for
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those two classes. The caller has to provide a priority function, which
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extracts each item's priority.
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"""
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def __init__(self, priorityFunction):
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"priorityFunction (item) -> priority"
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self.priorityFunction = priorityFunction # store the priority function
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PriorityQueue.__init__(self) # super-class initializer
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def push(self, item):
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"Adds an item to the queue with priority from the priority function"
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PriorityQueue.push(self, item, self.priorityFunction(item))
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def manhattanDistance( xy1, xy2 ):
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"Returns the Manhattan distance between points xy1 and xy2"
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return abs( xy1[0] - xy2[0] ) + abs( xy1[1] - xy2[1] )
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"""
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Data structures and functions useful for various course projects
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The search project should not need anything below this line.
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"""
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class Counter(dict):
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"""
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A counter keeps track of counts for a set of keys.
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The counter class is an extension of the standard python
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dictionary type. It is specialized to have number values
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(integers or floats), and includes a handful of additional
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functions to ease the task of counting data. In particular,
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all keys are defaulted to have value 0. Using a dictionary:
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a = {}
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print a['test']
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would give an error, while the Counter class analogue:
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>>> a = Counter()
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>>> print a['test']
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0
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returns the default 0 value. Note that to reference a key
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that you know is contained in the counter,
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you can still use the dictionary syntax:
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>>> a = Counter()
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>>> a['test'] = 2
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>>> print a['test']
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2
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This is very useful for counting things without initializing their counts,
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see for example:
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>>> a['blah'] += 1
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>>> print a['blah']
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1
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The counter also includes additional functionality useful in implementing
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the classifiers for this assignment. Two counters can be added,
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subtracted or multiplied together. See below for details. They can
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also be normalized and their total count and arg max can be extracted.
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"""
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def __getitem__(self, idx):
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self.setdefault(idx, 0)
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return dict.__getitem__(self, idx)
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def incrementAll(self, keys, count):
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"""
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Increments all elements of keys by the same count.
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>>> a = Counter()
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>>> a.incrementAll(['one','two', 'three'], 1)
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>>> a['one']
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1
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>>> a['two']
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1
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"""
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for key in keys:
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self[key] += count
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def argMax(self):
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"""
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Returns the key with the highest value.
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"""
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if len(self.keys()) == 0: return None
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all = self.items()
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values = [x[1] for x in all]
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maxIndex = values.index(max(values))
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return all[maxIndex][0]
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def sortedKeys(self):
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"""
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Returns a list of keys sorted by their values. Keys
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with the highest values will appear first.
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>>> a = Counter()
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>>> a['first'] = -2
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>>> a['second'] = 4
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>>> a['third'] = 1
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>>> a.sortedKeys()
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['second', 'third', 'first']
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"""
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sortedItems = self.items()
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compare = lambda x, y: sign(y[1] - x[1])
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sortedItems.sort(cmp=compare)
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return [x[0] for x in sortedItems]
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def totalCount(self):
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"""
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Returns the sum of counts for all keys.
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"""
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return sum(self.values())
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def normalize(self):
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"""
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Edits the counter such that the total count of all
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keys sums to 1. The ratio of counts for all keys
|
|
will remain the same. Note that normalizing an empty
|
|
Counter will result in an error.
|
|
"""
|
|
total = float(self.totalCount())
|
|
if total == 0: return
|
|
for key in self.keys():
|
|
self[key] = self[key] / total
|
|
|
|
def divideAll(self, divisor):
|
|
"""
|
|
Divides all counts by divisor
|
|
"""
|
|
divisor = float(divisor)
|
|
for key in self:
|
|
self[key] /= divisor
|
|
|
|
def copy(self):
|
|
"""
|
|
Returns a copy of the counter
|
|
"""
|
|
return Counter(dict.copy(self))
|
|
|
|
def __mul__(self, y ):
|
|
"""
|
|
Multiplying two counters gives the dot product of their vectors where
|
|
each unique label is a vector element.
|
|
|
|
>>> a = Counter()
|
|
>>> b = Counter()
|
|
>>> a['first'] = -2
|
|
>>> a['second'] = 4
|
|
>>> b['first'] = 3
|
|
>>> b['second'] = 5
|
|
>>> a['third'] = 1.5
|
|
>>> a['fourth'] = 2.5
|
|
>>> a * b
|
|
14
|
|
"""
|
|
sum = 0
|
|
x = self
|
|
if len(x) > len(y):
|
|
x,y = y,x
|
|
for key in x:
|
|
if key not in y:
|
|
continue
|
|
sum += x[key] * y[key]
|
|
return sum
|
|
|
|
def __radd__(self, y):
|
|
"""
|
|
Adding another counter to a counter increments the current counter
|
|
by the values stored in the second counter.
|
|
|
|
>>> a = Counter()
|
|
>>> b = Counter()
|
|
>>> a['first'] = -2
|
|
>>> a['second'] = 4
|
|
>>> b['first'] = 3
|
|
>>> b['third'] = 1
|
|
>>> a += b
|
|
>>> a['first']
|
|
1
|
|
"""
|
|
for key, value in y.items():
|
|
self[key] += value
|
|
|
|
def __add__( self, y ):
|
|
"""
|
|
Adding two counters gives a counter with the union of all keys and
|
|
counts of the second added to counts of the first.
|
|
|
|
>>> a = Counter()
|
|
>>> b = Counter()
|
|
>>> a['first'] = -2
|
|
>>> a['second'] = 4
|
|
>>> b['first'] = 3
|
|
>>> b['third'] = 1
|
|
>>> (a + b)['first']
|
|
1
|
|
"""
|
|
addend = Counter()
|
|
for key in self:
|
|
if key in y:
|
|
addend[key] = self[key] + y[key]
|
|
else:
|
|
addend[key] = self[key]
|
|
for key in y:
|
|
if key in self:
|
|
continue
|
|
addend[key] = y[key]
|
|
return addend
|
|
|
|
def __sub__( self, y ):
|
|
"""
|
|
Subtracting a counter from another gives a counter with the union of all keys and
|
|
counts of the second subtracted from counts of the first.
|
|
|
|
>>> a = Counter()
|
|
>>> b = Counter()
|
|
>>> a['first'] = -2
|
|
>>> a['second'] = 4
|
|
>>> b['first'] = 3
|
|
>>> b['third'] = 1
|
|
>>> (a - b)['first']
|
|
-5
|
|
"""
|
|
addend = Counter()
|
|
for key in self:
|
|
if key in y:
|
|
addend[key] = self[key] - y[key]
|
|
else:
|
|
addend[key] = self[key]
|
|
for key in y:
|
|
if key in self:
|
|
continue
|
|
addend[key] = -1 * y[key]
|
|
return addend
|
|
|
|
def raiseNotDefined():
|
|
fileName = inspect.stack()[1][1]
|
|
line = inspect.stack()[1][2]
|
|
method = inspect.stack()[1][3]
|
|
|
|
print "*** Method not implemented: %s at line %s of %s" % (method, line, fileName)
|
|
sys.exit(1)
|
|
|
|
def normalize(vectorOrCounter):
|
|
"""
|
|
normalize a vector or counter by dividing each value by the sum of all values
|
|
"""
|
|
normalizedCounter = Counter()
|
|
if type(vectorOrCounter) == type(normalizedCounter):
|
|
counter = vectorOrCounter
|
|
total = float(counter.totalCount())
|
|
if total == 0: return counter
|
|
for key in counter.keys():
|
|
value = counter[key]
|
|
normalizedCounter[key] = value / total
|
|
return normalizedCounter
|
|
else:
|
|
vector = vectorOrCounter
|
|
s = float(sum(vector))
|
|
if s == 0: return vector
|
|
return [el / s for el in vector]
|
|
|
|
def nSample(distribution, values, n):
|
|
if sum(distribution) != 1:
|
|
distribution = normalize(distribution)
|
|
rand = [random.random() for i in range(n)]
|
|
rand.sort()
|
|
samples = []
|
|
samplePos, distPos, cdf = 0,0, distribution[0]
|
|
while samplePos < n:
|
|
if rand[samplePos] < cdf:
|
|
samplePos += 1
|
|
samples.append(values[distPos])
|
|
else:
|
|
distPos += 1
|
|
cdf += distribution[distPos]
|
|
return samples
|
|
|
|
def sample(distribution, values = None):
|
|
if type(distribution) == Counter:
|
|
items = sorted(distribution.items())
|
|
distribution = [i[1] for i in items]
|
|
values = [i[0] for i in items]
|
|
if sum(distribution) != 1:
|
|
distribution = normalize(distribution)
|
|
choice = random.random()
|
|
i, total= 0, distribution[0]
|
|
while choice > total:
|
|
i += 1
|
|
total += distribution[i]
|
|
return values[i]
|
|
|
|
def sampleFromCounter(ctr):
|
|
items = sorted(ctr.items())
|
|
return sample([v for k,v in items], [k for k,v in items])
|
|
|
|
def getProbability(value, distribution, values):
|
|
"""
|
|
Gives the probability of a value under a discrete distribution
|
|
defined by (distributions, values).
|
|
"""
|
|
total = 0.0
|
|
for prob, val in zip(distribution, values):
|
|
if val == value:
|
|
total += prob
|
|
return total
|
|
|
|
def flipCoin( p ):
|
|
r = random.random()
|
|
return r < p
|
|
|
|
def chooseFromDistribution( distribution ):
|
|
"Takes either a counter or a list of (prob, key) pairs and samples"
|
|
if type(distribution) == dict or type(distribution) == Counter:
|
|
return sample(distribution)
|
|
r = random.random()
|
|
base = 0.0
|
|
for prob, element in distribution:
|
|
base += prob
|
|
if r <= base: return element
|
|
|
|
def nearestPoint( pos ):
|
|
"""
|
|
Finds the nearest grid point to a position (discretizes).
|
|
"""
|
|
( current_row, current_col ) = pos
|
|
|
|
grid_row = int( current_row + 0.5 )
|
|
grid_col = int( current_col + 0.5 )
|
|
return ( grid_row, grid_col )
|
|
|
|
def sign( x ):
|
|
"""
|
|
Returns 1 or -1 depending on the sign of x
|
|
"""
|
|
if( x >= 0 ):
|
|
return 1
|
|
else:
|
|
return -1
|
|
|
|
def arrayInvert(array):
|
|
"""
|
|
Inverts a matrix stored as a list of lists.
|
|
"""
|
|
result = [[] for i in array]
|
|
for outer in array:
|
|
for inner in range(len(outer)):
|
|
result[inner].append(outer[inner])
|
|
return result
|
|
|
|
def matrixAsList( matrix, value = True ):
|
|
"""
|
|
Turns a matrix into a list of coordinates matching the specified value
|
|
"""
|
|
rows, cols = len( matrix ), len( matrix[0] )
|
|
cells = []
|
|
for row in range( rows ):
|
|
for col in range( cols ):
|
|
if matrix[row][col] == value:
|
|
cells.append( ( row, col ) )
|
|
return cells
|
|
|
|
def lookup(name, namespace):
|
|
"""
|
|
Get a method or class from any imported module from its name.
|
|
Usage: lookup(functionName, globals())
|
|
"""
|
|
dots = name.count('.')
|
|
if dots > 0:
|
|
moduleName, objName = '.'.join(name.split('.')[:-1]), name.split('.')[-1]
|
|
module = __import__(moduleName)
|
|
return getattr(module, objName)
|
|
else:
|
|
modules = [obj for obj in namespace.values() if str(type(obj)) == "<type 'module'>"]
|
|
options = [getattr(module, name) for module in modules if name in dir(module)]
|
|
options += [obj[1] for obj in namespace.items() if obj[0] == name ]
|
|
if len(options) == 1: return options[0]
|
|
if len(options) > 1: raise Exception, 'Name conflict for %s'
|
|
raise Exception, '%s not found as a method or class' % name
|
|
|
|
def pause():
|
|
"""
|
|
Pauses the output stream awaiting user feedback.
|
|
"""
|
|
print "<Press enter/return to continue>"
|
|
raw_input()
|
|
|
|
|
|
# code to handle timeouts
|
|
#
|
|
# FIXME
|
|
# NOTE: TimeoutFuncton is NOT reentrant. Later timeouts will silently
|
|
# disable earlier timeouts. Could be solved by maintaining a global list
|
|
# of active time outs. Currently, questions which have test cases calling
|
|
# this have all student code so wrapped.
|
|
#
|
|
import signal
|
|
import time
|
|
class TimeoutFunctionException(Exception):
|
|
"""Exception to raise on a timeout"""
|
|
pass
|
|
|
|
|
|
class TimeoutFunction:
|
|
def __init__(self, function, timeout):
|
|
self.timeout = timeout
|
|
self.function = function
|
|
|
|
def handle_timeout(self, signum, frame):
|
|
raise TimeoutFunctionException()
|
|
|
|
def __call__(self, *args, **keyArgs):
|
|
# If we have SIGALRM signal, use it to cause an exception if and
|
|
# when this function runs too long. Otherwise check the time taken
|
|
# after the method has returned, and throw an exception then.
|
|
if hasattr(signal, 'SIGALRM'):
|
|
old = signal.signal(signal.SIGALRM, self.handle_timeout)
|
|
signal.alarm(self.timeout)
|
|
try:
|
|
result = self.function(*args, **keyArgs)
|
|
finally:
|
|
signal.signal(signal.SIGALRM, old)
|
|
signal.alarm(0)
|
|
else:
|
|
startTime = time.time()
|
|
result = self.function(*args, **keyArgs)
|
|
timeElapsed = time.time() - startTime
|
|
if timeElapsed >= self.timeout:
|
|
self.handle_timeout(None, None)
|
|
return result
|
|
|
|
|
|
|
|
_ORIGINAL_STDOUT = None
|
|
_ORIGINAL_STDERR = None
|
|
_MUTED = False
|
|
|
|
class WritableNull:
|
|
def write(self, string):
|
|
pass
|
|
|
|
def mutePrint():
|
|
global _ORIGINAL_STDOUT, _ORIGINAL_STDERR, _MUTED
|
|
if _MUTED:
|
|
return
|
|
_MUTED = True
|
|
|
|
_ORIGINAL_STDOUT = sys.stdout
|
|
#_ORIGINAL_STDERR = sys.stderr
|
|
sys.stdout = WritableNull()
|
|
#sys.stderr = WritableNull()
|
|
|
|
def unmutePrint():
|
|
global _ORIGINAL_STDOUT, _ORIGINAL_STDERR, _MUTED
|
|
if not _MUTED:
|
|
return
|
|
_MUTED = False
|
|
|
|
sys.stdout = _ORIGINAL_STDOUT
|
|
#sys.stderr = _ORIGINAL_STDERR
|
|
|