字符串和字符

第12讲字符串和字符1、Mathematica中的字符串2、字符串操作3、字符串模式4、字符串中的字符5、特殊字符6、字符串中的换行和制表符7、字符编码8、原始字符编码December10,20041StartLearningStepbyStep1、Mathematica中的字符串Textstrings

“text” astringcontainingarbitrarytext字符串的头部：

StringDecember10,20042StartLearningStepbyStep2、字符串操作整个字符串上的运算

s1<>s2<>…orStringJoin[{s1,s2,…}] joinstringstogether

StringLength[s] givethelengthofstring

StringReverse[s] reversethecharactersinastring取与弃子串

StringTake[s,n] makeastringbytakepartofstrings

StringDrop[s,n] makeastringbydroppartofstringsWherencanbeaninteger,{n},or{n1,n2}字符串中插入

StringInsert[s,snew,n] insertthestringsnewatpositionnins Wherencanbeaninteger,or{n1,n2,…}forseveralcopiesDecember10,20043StartLearningStepbyStep2、字符串操作.字符串中替换（位置）

StringReplacePart[s,snew,{m,n}] replacethepartofstringCanalsobeformsof

StringReplacePart[s,snew,{{m1,n1},{m2,n2},…}]

StringReplacePart[s,{snew1,snew2,…},{{m1,n1},{m2,n2},…}]子串定位

StringPosition[s,sub] givealistofthestartingandending

StringPosition[s,sub,k]

includingonlythefirstkoccurrences

StringPosition[s,{sub1,sub2,…}] includeoccurrencesofanyof…字符串替换（规则）

StringReplace[s,{s1->sp1,s2->sp2,..}] replacebycorrespondingDecember10,20044StartLearningStepbyStep3、字符串模式匹配字符串

“string1”==“string2” testwhethertwostringsareidentical

StringMatchQ[“string”,“pattern”] testwhetherastringmatches字符串模式中的元字符

* zeroormorecharacters @

oneormorecharacters(notUCL) \*etc. literal*etc.字符串匹配时的选项

SpellingCorrection->True allowasmallfractionofcharactersdiffer

IgnoreCase->True ignoredifferenceofloweranduppercaseDecember10,20045StartLearningStepbyStep4、字符串中的字符字符串和字符数组间的转换

Characters[“string”] convertastringtoalistofcharacters

StringJoin[{“c1”,“c2”,…}] convertalistofcharacterstoastring字符串中字符的测试

DigitQ[string] testwhetherallcharactersaredigits

LetterQ[string] testwhetherallcharactersareletters

UpperCaseQ[string] testwhetherallupper-caseletters

LowerCaseQ[string] testwhetheralllower-caseletters字符串中字符大小写的转换

ToUpperCase[string] generateastringalllettersuppercase

ToLowerCase[string] generateastringallletterslowercase生成特定范围内的字符

CharacterRange[“c1”,“c2”] generatealistofallcharactersfromc1toc2December10,20046StartLearningStepbyStep5、特殊字符字符串中输入字符的方法

a aliteralcharacter \[Name] acharacterspecifiedusingitsfullname \” a“tobeincludedinastring \\ a\tobeincludedinastringDecember10,20047StartLearningStepbyStep6、字符串中的换行和制表符字符串中换行和制表符的显式表示

\n anewline(linefeed)tobeincludedinstring \t atabtobeincludedinastring字符串的输入形式

“text” linebreaksintextareignored “\<text\>” linebreaksintextarestoredexplicitlyas\nDecember10,20048StartLearningStepbyStep7、字符编码转换为编码和从编码转换为字符串

ToCharacterCode[“string”] givealistofthecharactercodesforstring

FromCharacterCode[n] constructacharacterfromitscharactercode

FromCharacterCode[{n1,n2,…}] constructastringfromalistofcharactercodesStillremembertheCharacterRange?用字符编码输入字符的方法

\0 nullbyte(code0) \nnn acharacterwithoctalcodennn \.nn acharacterwithhexadecimalcodenn \:nnnn

acharacterwithhexadecimalcodennnnDecember10,20049StartLearningStepbyStep7、字符编码.Mathematica中用的字符编码的一些范围

0-127(\000-\177) ASCIIcharacters 1-31(\001-\037) ASCIIcontrolcharacters 32-126(\040-\176) printableASCIIcharacters 97-122(\141-\172) lower-caseEnglishletters 129-255(\201-\377) ISOLatin-1characters 192-255(\240-\377) lettersinEuropeanlanguages 0-59391(\:0000-\:e7ff) Unicodestandardpubliccharacters 913-1009(\:0391-\:03f1) Greekletters 12288-35839(\:3000-\:8bff) Chinese,JapaneseandKoreancharacters 8450-8504(\:2102-\:2138) modifiedlettersusedinmathematicalnotation 8592-8677(\:2190-\:21e5) arrows 8704-8945(\:2200-\:22f1) mathematicalsymbolsandoperators 64256-64300(\:fb00-\:fb2c) UnicodeprivatecharactersdefinedbyMathematica™December10,200410StartLearningStepbyStep8、原始字符编码设置原始编码

$CharacterEncoding=“name” usetherawcharacterencodingspecified $SystemCharacterEncoding thedefaultrawcharacterencodingforsystemMathematica支持的一些原始编码

“PrintableASCII” printableASCIIcharactersonly(default) “ASCII” allASCIIincludingcontrolcharacters “ISOLatin1” charactersforcommonwesternEuropeanlanguages “ISOLatin2” “ISOLatin3” …… “Unicode” raw16-bitUnicodebitpatterns用不同的编码方式处理字符编码

ToCharacterCode[“string”,“encoding”] usingthespecifiedencoding

FromCharacterCode[{n1,n2,…},“encoding”] usingthespecifiedencodingDecember10,200411StartLearningStepbyStep作业ProjectID:10Emailto:011466@Dued