【第2章】《计算思维》实验报告1 Python【上海理工】

实验报告实验2-《计算思维》实验过程题目：Theareaofarectangleis

wh,where

w

and

h

arethelengthsofitssides.Notethatthemultiplicationoperationisnotshownexplicitlyinthisformula.Thisisstandardpracticeinmathematics,butnotinprogramming.WriteaPythonstatementthatcalculatesandprintstheareainsquareinchesofarectanglewithsidesoflength

4

and

7

inches.代码：print4*7运行结果：题目：Thecircumferenceofacircleis

2πr

where

r

istheradiusofthecircle.WriteaPythonstatementthatcalculatesandprintsthecircumferenceininchesofacirclewhoseradiusis

8

inches.Assumethattheconstant

π=3.14.代码：print2*3.14*8运行结果：题目：Theareaofacircleis

πr2

where

r

istheradiusofthecircle.(Theraised

2

intheformulaisanexponent.)WriteaPythonstatementthatcalculatesandprintstheareainsquareinchesofacirclewhoseradiusis

8

inches.Assumethattheconstant

π=3.14.代码：print3.14*8**2运行结果：题目：Given

p

dollars,thefuturevalueofthismoneywhencompoundedyearlyatarateof

r

percentinterestfor

y

yearsis

p(1+0.01r)y.WriteaPythonstatementthatcalculatesandprintsthevalueof

1000

dollarscompoundedat

7

percentinterestfor

10

years.代码：print1000*(1+0.01*7)**10或a=1c=1b=(1+0.01*7)p=1000whilea<=10:c=c*ba=a+1p=p*cprintp运行结果：题目：WriteasinglePythonstatementthatcombinesthethreestrings

"Mynameis",

"Joe"

and

"Warren"

(plusacoupleofothersmallstrings)intoonelargerstring

"MynameisJoeWarren."

andprintstheresult.代码：print"Mynameis"+"Joe"+""+"Warren"+"."运行结果：题目：WriteaPythonexpressionthatcombinesthestring

"JoeWarrenis52yearsold."

fromthestring

"JoeWarren"

andthenumber

52

andthenprintstheresult(Hint:Usethefunction

str

toconvertthenumberintoastring.)代码：print"JoeWarren"+"is"+str(52)+"yearsold."运行结果：题目：Thedistancebetweentwopoints

(x0,y0)

and

(x1,y1)

is

√(x0-x1)2+(y0-y1)2

代码：print((2-5)**2+(2-6)**2)**0.5或a=(2-5)*(2-5)+(2-6)*(2-6)printpow(a,0.5)运行结果：WriteaPythonfunction

is_lunchtime

thattakesasinputtheparameters

hour

(anintegerintherange

[1,12])and

is_am

(aBoolean“flag”thatrepresentswhetherthehourisbeforenoon).Thefunctionshouldreturn

True

whentheinputcorrespondsto11amor12pm(noon)and

Falseotherwise.Iftheproblemspecificationisunclear,lookatthetestcasesintheprovidedtemplate.Oursolutiondoesnotuseconditionalstatements.代码：defis_lunchtime(hour,is_am): """ Returnswhetherthegiventime,asrepresentedbythehour andis_am,islunchtime. """ return(hour==11andis_am)or(hour==12andnotis_am)deftest(hour,is_am): """Teststheis_lunchtimefunction.""" printhour, ifis_am: print"AM", else: print"PM", ifis_lunchtime(hour,is_am): print"islunchtime." else: print"isnotlunchtime."test(11,True)test(12,True)test(11,False)test(12,False)test(10,False)运行结果：WriteaPythonfunction

is_leap_year

thattakeasinputtheparameter

year

andreturns

True

if

year

(aninteger)isaleapyearaccordingtotheGregoriancalendarand

False

otherwise.TheWikipediaentryfor

leapyears

containsasimplealgorithmicrulefordeterminingwhetherayearisaleapyear.YourmaintaskwillbetotranslatethisruleintoPython.代码：defis_leap_year(year): """ ReturnswhetherthegivenGregorianyearisaleapyear. """ return((year%4)==0and((year%100)!=0or(year%400)==0))deftest(year): """Teststheis_leapyearfunction.""" ifis_leap_year(year): printyear,"isaleapyear." else: printyear,"isnotaleapyear."test(2000)test(1996)test(1800)test(2013)运行结果：WriteaPythonfunction

interval_intersect

thattakesparameters

a,

b,

c,and

d

andreturns

True

iftheintervals

[a,b]

and

[c,d]

intersectandFalse

otherwise.Whilethistestmayseemtricky,thesolutionisactuallyverysimpleandconsistsofonelineofPythoncode.(Youmayassumethat

a≤b

and

c≤d.)代码：definterval_intersect(a,b,c,d):"""Returnswhethertheintervals[a,b]and[c,d]intersect."""return(c<=b)and(a<=d)deftest(a,b,c,d):"""Teststheinterval_intersectfunction."""print"Intervals["+str(a)+","+str(b)+"]and["+str(c)+","+str(d)+"]",ifinterval_intersect(a,b,c,d):print"intersect."else:print"donotintersect."test(0,1,1,2)test(1,2,0,1)test(0,1,2,3)test(2,3,0,1)test(0,3,1,2)运行结果：WriteaPythonfunction

name_and_age

thattakeasinputtheparameters

name

(astring)and

age

(anumber)andreturnsastringoftheform

"%is%yearsold."

wherethepercentsarethestringformsof

name

and

age.Thefunctionshouldincludeanerrorcheckforthecasewhen

age

islessthanzero.Inthiscase,thefunctionshouldreturnthestring

"Error:Invalidage".代码：defname_and_age(name,age): """Returnsastringstatingtheperson'sage.""" ifage>=0: returnname+"is"+str(age)+"yearsold." else: return"Error:Invalidage"deftest(name,age): """Teststhename_and_agefunction.""" printname_and_age(name,age) test("JoeWarren",52)test("ScottRixner",40)test("JohnGreiner",-46)运行结果：WriteaPythonfunction

print_digits

thattakesaninteger

number

intherange

[0,100)

andprintsthemessage

"Thetensdigitis%andtheonesdigitsis%"

wherethepercentsshouldbereplacedwiththeappropriatevalues.Thefunctionshouldincludeanerrorcheckforthecasewhend

isnegativeorgreaterthanorequalto

100.Inthosecases,thefunctionshouldinsteadprint

"Error:Inputisnotatwo-digitnumber.".代码：defprint_digits(number): """Printsthetensandonesdigitofanintegerin[0,100).""" if0<=number<100: print"Thetensdigitis"+str(number//10)+",", print"andtheonesdigitis"+str(number%10)+"." else: print"Error:Inputisnotatwo-digitnumber." print_digits(42)print_digits(99)print_digits(5)print_digits(459)运行结果：WriteaPythonfunction

name_lookup

thattakesastring

first_name

thatcorrespondstooneof("Joe",

"Scott",

"John"

or

"Stephen")andthenreturnstheircorrespondinglastname("Warren",

"Rixner",

"Greiner"

or

"Wong").If

first_name

doesn'tmatchanyofthosestrings,returnthestring

"Error:Notaninstructor".代码：defname_lookup(first_name): """Returnstheinstructor'slastname.""" iffirst_name=="Joe": return"Warren" eliffirst_name=="Scott": return"Rixner" eliffirst_name=="John": return"Greiner" eliffirst_name=="Stephen": return"Wong" else: return"Error:Notaninstructor"deftest(first_name): """Teststhename_lookupfunction.""" printname_lookup(first_name) test("Joe")test("Scott")test("John")test("Stephen")test("Mary")运行结果：PigLatin

isalanguagegamethatinvolvesalteringwordsviaasimplesetofrules.WriteaPythonfunction

pig_latin

thattakesastring

word

andappliesthefollowingrulestogenerateanewwordinPigLatin.Ifthefirstletterin

word

isaconsonant,appendtheconsonantplus

"ay"

totheendoftheremainderoftheword.Forexample,

pig_latin("pig")wouldreturn

"igpay".Ifthefirstletterin

word

isavowel,append

"way"

totheendoftheword.Forexample,

pig_latin("owl")

returns

"owlway".Youcanassumethat

word

isinlowercase.Theprovidedtemplateincludescodetoextractthefirstletterandtherestof

word

inPython.Notethat,infullPigLatin,theleadingconsonantclusterismovedtotheendoftheword.However,wedon'tknowenoughPythontoimplementfullPigLatinjustyet.代码：defpig_latin(word): """Returnsthe(simplified)PigLatinversionoftheword.""" first_letter=word[0] rest_of_word=word[1:] #Studentshouldcompletefunctiononthenextlines. if(first_letter=="a"orfirst_letter=="e"orfirst_letter=="i"or first_letter=="o"orfirst_letter=="u"): returnword+"way" else: returnrest_of_word+first_letter+"ay"deftest(word): """Teststhepig_latinfunction.""" printpig_latin(word) test("pig")test("owl")test("python")运行结果：Challenge:

Givennumbers

a,

b,and

c,the

quadraticequation

ax2+bx+c=0

canhavezero,oneortworealsolutions(i.e;valuesfor

x

thatsatisfytheequation).The

quadraticformulax=−b±b2−4ac√2acanbeusedtocomputethesesolutions.Theexpression

b2−4ac

isthe

discriminant

associatedwiththeequation.Ifthediscriminantispositive,theequationhastwosolutions.Ifthediscriminantiszero,theequationhasonesolution.Finally,ifthediscriminantisnegative,theequationhasnosolutions.WriteaPythonfunction

smaller_root

thattakesaninputthenumbers

a,

b

and

c

andreturnsthesmallersolutiontothisequationifoneexists.Iftheequationhasnorealsolution,printthemessage

"Error:Norealsolutions"

andsimplyreturn.Notethat,inthiscase,thefunctionwillactuallyreturnthespecialPythonvalue

None.代码：defsmaller_root(a,b,c):"""Returnsthesmallerrootofaquadraticequationwiththegivencoefficients."""disc