mule cookbook

Python Cookbook (2nd) Chinese Version Basic Information Author: Alex Martelli Anna Ravenscroft David AscherTranslator: Gao tiejun [same translator's work]Press: People's post and telecommunications PressISBN: 9787115222664Mounting time:Published on: February 1, May 2010Start: 16For more details, see: http://www.china-pub.com/196697The first five chapter sample read address: http://www.china-pub.com/computers/common/mianfeisd.asp? Id = 196697 Edit reco

When you look at the Python Cookbook, section 9.5, "Defining an adorner that can be modified by the user", has an adorner that takes some time to make a note lest you forget the second time you brush the book.Complete code: https://github.com/blackmatrix7/python-learning/blob/master/python_cookbook/chapter_9/section_5/attach_wrapper.pyThe decorator in the book (called the Accessor function in the book)def attach_wrapper (obj, func=None): if is none

':'Jones','UID': 1003}, {'fname':'David','lname':'Beazley','UID': 1002}, {'fname':'John','lname':'Cleese','UID': 1001}]sorted by uid:[{'fname':'John','lname':'Cleese','UID': 1001}, {'fname':'David','lname':'Beazley','UID': 1002}, {'fname':'Brian','lname':'Jones','UID': 1003}, {'fname':'Big','lname':'Jones','UID': 1004}]sorted by lname,fname:[{'fname':'David','lname':'Beazley','UID': 1002}, {'fname':'John','lname':'Cleese','UID': 1001}, {'fname':'Big','lname':'Jones','UID': 1004}, {'fname':'Brian

the value of key is the set typec['a'].add (1) c['a'].add (2) c['a'].add (2) c['b'].add (4)Print('the value of key is a dictionary of the list type:', D)Print('the value of key is a dictionary of the set type:'C>>> ================================ RESTART ================================>>>the value of key is a dictionary of list type: Defaultdict (class 'List', {'b': [4],'a': [1, 2, 2]}) The value of key is a dictionary of the set type: Defaultdict (class 'Set', {'b': {4},'a': {1, 2}})>>>One t

errorTraceback (most recent): File"", Line 1,inchIndexerror:index out of range>>> Heappush (a,3)>>>a[3]>>> Heapreplace (a,2)#Delete (Heappop (a)->3) first, then join (Heappush (a,2))3>>>a[2]>>> Heappush (a,5) >>> Heappush (a,9)>>> Heappush (a,4)>>>a[2, 4, 9, 5]>>> Heapreplace (a,6)#first find the minimum value from heap A and return, then add 62>>>a[4, 5, 9, 6]>>> Heapreplace (a,1)#1 is added later, before 1, the minimum value in a is 4 .4>>>a[1, 5, 9, 6]>>> a=[2,4,6] >>> b=[1,3,5]>>>

Problem: You want to access the element by name to reduce the dependency on the location in the structureSolution: Use the named Tuple collections.namedtuple (). It is a factory method that returns a subclass of the standard tuple type in Python, gives it a type name and the corresponding field name , returns a class that can be instantiated, gives you a defined field name to pass in the value, and so on.The primary purpose of a named tuple is to decouple the code from the location of the elemen

Problem: Want to create a dictionary, which is itself a subset of another dictionarySolution: Use dictionary derivation (dictionary comprehension) to easily solve#example of extracting a subset from a dictionary fromPprintImportpprintprices= { 'ACME': 45.23, 'AAPL': 612.78, 'IBM': 205.55, 'HPQ': 37.20, 'FB': 10.75}#Make A dictionary of pricesP1 = {Key:value forKey, ValueinchPrices.items ()ifValue > 200 }Print("All prices") Pprint (p1)#Make A dictionary of tech stocksTech_names = {'AAPL

=min (Zip (Prices.keys (), Prices.values ())) #zip () parameter is incorrect in order to get the wrong value>>>Min_price3 ('AAPL', 612.78)>>> Max_price3 =max (Zip (Prices.keys (), Prices.values ())) #zip () parameter is incorrect in order to get the wrong value >>>Max_price3 ('IBM', 205.55)>>>When doing these calculations, note that zip () creates an iterator whose contents can only be consumed once. For example:>>> pirces_and_names=Zip (prices.values (), Prices.keys ())>>> pirces_and_names mi

If the object is an iterative (any sequence), it can be decomposed, including tuples, lists, strings, files, iterators, and generators, which can be decomposed into separate variables by a simple assignment operation.The only requirement: The total number of variables matches the sequence, otherwise an error will occur;Python 2.7.11 (v2.7.11:6d1b6a68f775, Dec 5, 20:32:19) [MSC v.1500 32bit (Intel)] on Win32type"Copyright","credits" or "license ()" forMore information.>>> p=[4,5]>>>p[4, 5]>>> x,

experimentImportunicodedatan_s1= Unicodedata.normalize ('NFC', s1) n_s2= Unicodedata.normalize ('NFC', S2)Print('n_s1 = = n_s2?', n_s1 = =n_s2)Print('len (n_s1) =', Len (N_S1),'Len (N_S2)', Len (n_s2))Print('*****************************')#(d) Example of normalizing to a decomposed form and stripping accentsT1 = Unicodedata.normalize ('NFD', s1) T2= Unicodedata.normalize ('NFD', S2)Print('T1 = = t2?', t1==T2)Print('len (t1) =', Len (T1),'len (t2) =', Len (T2))Print("'. Join (c forCinchT1if not

keyword;#example.py##Example of combining text via generatorsdefsample ():yield " is" yield "Chicago" yield " not" yield "Chicago?"#(a) use Join () to simply connect them togetherText ="'. Join (sample ())Print(text)Print('======================')#(b) Redirect these fragments to I/OImportSYS forPartinchsample (): Sys.stdout.write (part) Sys.stdout.write ('\ n')Print('**************************')#(c) intelligently combine I/O operations in a mixed mannerdefCombine (source, maxsize): Par

(Datepat.sub (change_date, text))Print(Re.sub (R'(\d+)/(\d+)/(\d+)', Change_date, text))Print('++++++++++++++++++++++++++++++++')# Total number of replacements obtained by RE.SUBN () newtext,n =datepat.subn (r " \3-\1-\2 " , text) print (NewText) print (N) >>> ================================ RESTART ================================>>> yeh,but No, But yeh,but no,but yeh,but no,but yehyeah,but yes,but yeah,but yes,but yeah,but no,but yeah------------------------- - -is 2012-11-27. Pycon

Python cookbook (data structure and algorithm) method for saving the last N elements, pythoncookbook This example describes how to save the last N elements in Python. We will share this with you for your reference. The details are as follows: Problem:We hope to make a limited history statistics for the last few records during iteration or other forms of processing. Solution:Select collections. deque. The following code performs a simple text match on