ic cookbook

DBecause if 2 different keys correspond to the same value, one of the 2 keys will definitely disappear for the 2 functions given by the solution.Thus the generated pseudo-inverse dictionary length will be shorter than the original dictionary length, in any case, only if the value in D is hashed, then the previous function will work properly, otherwise the function would give a TypeError exceptionThis function obtains the Iteritems method to generate a pair of keys and other corresponding values

perform mathematical operations that contain fractions.>>> from fractions import fraction>>> a =fraction (5,4) >>> B = fraction (7, +) >>> AFra Ction (5, 4) >>> bfraction (7) >>> print a+b27/16>>> print a*b35/64 numerator denominator >>> c= a*b Gt;>> c.numerator35>>> c.denominator64 Convert to decimal >>> float (c) 0.546875 limit denominator >>> c.limit_ Denominator (8) #分母不超过8的最接近的分数Fraction (4, 7) float converted to fractions >>> x=1.75>>> y = fraction (*x.as_integer_ Ratio ()) >>> yfraction

(Task); Thread.setuncaughtexceptionhandler (NewExceptionhandler ()); Thread.Start (); }} Public classTaskImplementsRunnable {@Override Public voidrun () {Integer.parseint ("TTT"); } }When an exception is thrown in the thread, the JVM first checks to see if the thread has set the thread exception handler and, if there is one, calls the processor to handle the exception. If not, the default behavior of the JVM is to print the thread stack information to the console while the program is roll

strings:S[::-1]Reverse the word only:Import reRev = Re.split (R ' (\s+) ', ' Hello World hahaha! ‘)Rev.reverse ()Rev = '. Join (REV) #要用空字符来join because the space is already in the cut listReturns all elements in a that are not part of B:Set (a). Difference (set (b))Translate method:Import strings = ' Hello world! 'Table = String.maketrans (' abcde ', ' 12345 ') #先生成对照表S.translate (table) #依照对照表进行替换操作S.translate (table, ' wor ') #替换后, delete characters containing worIf you want to delete only,

Chinese version of ActionScript 3 cookbook Download in PDF format (Full Version) Happy learning! 2008.01.25 update This article is declined without consent Chapter 1. Basics of The ActionScript Language Chapter 2. Custom classes Chapter 3. Runtime Environment Chapter 4. Numbers and mathematics Chapter 5. Array Chapter 6. Visual Object List (directory) Chapter 7. Drawing and masking(Directory) Chapter 8. Bitmap (directory) Chapter 9. Text (directory

The iPhone developer's cookbook Reading Notes, I will translate them slowly. PropertyOC automatically builds methods when you @ synthesize properties. notice the capitalization of the second word in the set method. by convention, OC expects setters to use a method named setinstance: where the first letter of the instance variable name is capitalized. Property attributesThe default behavior for properties is assign. Setting the property's attribu

The official release of the Simplified Chinese version of the event 3.0 cookbook in the event of a short period of time was announced. This is undoubtedly a great deal for colleagues who like flash and like as. Now let's get started first.Chapter 1. Basics of The ActionScript LanguageChapter 2. Custom classesChapter 3. Runtime EnvironmentChapter 4. Numbers and mathematicsChapter 5. ArrayChapter 6. Visual Object ListChapter 7. Drawing and maskingChapte

class Temperature(Object): coefficients={‘c‘:(1.0,0.0,-273.15),‘f‘:(1.8,-273.15,32.0),‘r‘:(1.8,0.0,0.0)} def __init__(self,**kwargs): try: name,value = kwargs.popitem() except KeyError: name,value = ‘k‘,0 if kwargs or name not in ‘kcfr‘: kwargs[name] = value raise TypeError,‘invalid arguments %r‘ % kwargs setattr(self,name,float(value)) def __getattr__(self,name): try: eq = self.cofficients[name]

DiC. ADD (Serializs. Current.name, Serializs. Current.value); - } $ returndic; the } the}If new requirements are required to add fields or attributes in modeling, we just need to add the fields that need to be serialized in GetObjectData, and in Getserializabledata, add the processing of deserialization. This way, we can open the previous data in a new project, no matter how many fields are added.SummaryTechnology is not cattle, only the problem you have met no,

is a very systematic ASP. NET sample tutorial? Lt; br> similar to Quickstart, But how detailed is it? Lt; br> you can name it like some books-"from entry to mastery? Lt; br> ASP. NET developer's cookbook Chapter 1: Web form BasicsChapter 2: User ControlsChapter 3: Custom ControlsChapter 4: cachingChapter 5: mobile controlsChapter 6: ASP. NET application configurationChapter 7: State managementChapter 8: SecurityChapter 9: Debugging and error handlin

I never saw the decorator. Today I flipped through the cookbook and read it for a while. 20.1 obtain new default values in function calls Task: After the def statement of the function is executed, Python calculates the default value for the optional parameter of the function, but only once. For some functions, each time you want to call a function, the default value is calculated. CodeAs follows: Import copydef freshdefaults (F): "An F-encapsul

values clipped to 0Neg_clip = [nifn > 0Else0 forNinchMyList]Print('The negative number is replaced by 0, and the result:', Neg_clip)#Positive values clipped to 0Pos_clip = [nifN Else0 forNinchMyList]Print('The positive number is replaced by 0, and the result:', Pos_clip)" ">>> ================================ RESTART ================================>>> mylist = [1, 4, -5, ten,-7, 2, 3,-1] Negative number is replaced by 0, result: [1, 4, 0, 0, 2, 3, -5 0, 7,-0, 0, 1,]The recommended tool, Iterto

Problem: Remove duplicate elements from the sequence, but still leave the remaining elements in the same orderSolution:1. If a value in a sequence can be hashed (hashable), it can be resolved by using the collection and the generator.2, if the sequence is not hashed, want to remove duplicates, you need to modify the above code slightly:The function of the key parameter is to specify a function to convert the elements in the sequence into a hash type, so that duplicates can be detected."Python

; ================================ RESTART ================================>>> 555555['. Idlerc','. Oracle_jre_usage','AppData','Application Data','Contacts','Cookies','Desktop','Documents','Downloads','Favorites','HelloWorld','Helloworld.zip','Links','Local Settings','log.html','Music','My Documents','MySite','Mysite.zip','NetHood','NTUSER. DAT','ntuser.dat.LOG1','ntuser.dat.LOG2','NTUSER. dat{6cced2f1-6e01-11de-8bed-001e0bcd1824}. TM.BLF','NTUSER. dat{6cced2f1-6e01-11de-8bed-001e0bcd1824}. Tmc

Problem: Look for two dictionaries in the middle of the same place (same key, same value, etc.)Solution: Use the keys () or the items () method to perform common collection operations (such as seek a set, intersection, and difference sets)>>> a={'x': 1,'y': 2,'Z': 3}>>> b={'ww': 10,'x': 11,'y': 2}>>> A.keys () B.keys () #键的交集 {'y','x'}>>> A.keys ()-B.keys () #键的差集 {'Z'}>>> A.keys () |B.keys () #键的并集 {'ww','y','x','Z'}>>> A.items () B.items () {('y', 2)}>>> A.items ()-B.items () {('Z', 3), ('x',

fixed-length queue that automatically removes the oldest record when a new element is added and the queue is full: from Import deque>>> q=deque (maxlen=3)>>> q.append (1)>>> q.append (2 )>>> q.append (3)>>> qdeque ([1, 2, 3], maxlen=3)>>> Q.append (4)>>> qdeque ([2, 3, 4], maxlen=3)>>> q.append (5) >>> qdeque ([3, 4, 5], maxlen=3)>>>Although this can be done manually on the list (append, Del), this solution for the queue is much more elegant and runs much faster.If you do not specify a queue l

first. >>> import JSON >> > Dordereddict ([( " foo , 1), (" bar , 2), (" spam , 3), ( ' grok , 4)]) >>> Json.dumps (d) " {" foo ": 1," Bar ": 2," Spam ": 3," Grok ": 4} >>> Add: Ordereddict internally maintains a doubly linked list, which arranges the position of the keys according to the order in which they are added. The first newly added element is placed at the end of the list, and subsequent re-assignment of the existing key does not change the order of the keys.Note: The s

slice object s, you can get information about the object by S.start, S.stop, and S.step properties, respectively.>>> items=[0,1,2,3,4,5,6]>>> a=slice (2,4)>>> Aslice (2, 4 , None)>>> a.start2>>> a.stop4>>> a.step>>> b= Slice (1,5,2)>>> bslice (1, 5, 2)>>> b.start1>>> b.stop5>>> b.stepIn addition, you can map slices to a sequence of a specific size by using the indices (size) method. This returns a (start,stop,step) tuple in which all values have been properly restricted within the bounds (as a

; Format (text,'')'Hello World'>>> Format (text,'^20')'Hello World'>>> Format (text,'*>20')#other padding characters that are extra empty can be specified before the alignment'*********hello World'>>> Format (text,'=')'Hello world========='>>> Format (text,'%^20')'%%%%hello world%%%%%'>>>#when multiple values are formatted, the formatting code code can be used in the format () method>>>'{: >10} {: >10}'. Format ('Hello',' World')'Hello World'>>>‘{: >10} {:%^10}‘. Format(‘Hello' ,'World')' Hello%

Problem: Use regular expressions to match text patterns to identify the longest possible match to find the shortest possible matchWorkaround: Add after the * operator in the matching pattern. ModifierImportRe#Sample TextText ='computer says "No." Phone says "Yes."'#(a) Regex that finds quoted Strings-longest matchStr_pat = Re.compile (r'\"(.*)\"')Print(Str_pat.findall (text))#(b) Regex that finds quoted Strings-shortest matchStr_pat = Re.compile (r'\"(.*?) \"')Print(Str_pat.findall (text))>>> ==