随笔分类 -  Python notes

摘要：os.madedirs:os.makedirs(path, mode=0o777, exist_ok=False)Recursive directory creation function. Like mkdir(), but makes all intermediate-level directories needed to contain the leaf directory. If the target directory with the same mode as specified already exists, raises an OSError exception if exis 阅读全文

摘要：Notes on argparse 阅读全文

摘要：When installing some supported packages in python3.2.2, usually got a error: (cannot remember clearly but like array object or so)Try to change the following file:%python%/Lib/distutils/command/build_scripts.py line 15:first_line_re = re.compile(b'^#!.*python[0-9.]*([ \t].*)?$')to:first_line 阅读全文

摘要：Tuples:T = (1, 2, 3, 4)len(T)T + (5, 6)T.index(4)T.count(4)#Tuples are immutableSets:T = (1, 2, 3, 4)len(T)T + (5, 6)T.index(4)T.count(4)#Tuples are immutableFractions:from fractions import Fractionf = Fraction(2, 3)f+1f + Fraction(1, 2)Types:L = [2, 3, 4]type(L) #<class 'list'> for 3. 阅读全文

摘要：Mapping a dictionary:D = {'food': 'Spam', 'quantity':4} #build with {}D = dict(food='Spam', quantity=4) #build with dict()D={}D['key'] = 'value' #add key,value to a dict.#Sorting Keys:for key in sorted(D): print(key, '=>', D[key])#Missing Ke 阅读全文

摘要：Examples from Learning Python 4th editionM = [[1,2,3],[2,3,4],[3,4,5]col2 = [row[1] for row in M][row[1] + 1 for row in M][row[1] for row in M if row[1] % 2 == 0]diag = [M[i][i] for i in [0,1,2]]G = (sum(row) for row in M) #Create a generator of row sumsnext(G) #Run the ite... 阅读全文