上游充通大学 ParisTech SHANGHAI JIAO TONG UNIVERSITY INSTITUT DES SCIENCES ET TECHNOLOGIES PARIS INSTITUTE OF TECHNOLOGY Logical operators 。and,or,not >>>X=5 >>>x%2==00rx%5==0 True >>>x%2==0andx%5==0 Fals a and b a b a or b a b not a a False False False False False False True False False False True True False True False True False True False True True False True True True True True True 6
Logical operators • and, or, not >>> x = 5 >>> x%2 == 0 or x%5 == 0 True >>> x%2 == 0 and x%5 == 0 Fals 6
上游充通大 ParisTech SHANGHAI JIAO TONG UNIVERSITY INSTITUT DES SCIENCES ET TECHNOLOGIES PARIS INSTITUTE OF TECHNOLOGY True or False True:1,!=0 not empty (string) ·False:0 Operation Result Notes x or y if x is false,then y,else x (1) X and y if x is false,then x,else y (2) not x if x is false,then True,else (3) False ·>>>a=3 ·>>>a==True ·False Why!!! 7
True or False • True: 1, !=0 not empty (string) • False: 0 • >>>a=3 • >>>a==True • False Why!!! 7
图 上游通大￥ ParisTech SHANGHAI JIAO TONG UNIVERSITY INSTITUT DES SCIENCES ET TECHNOLOGIES PARIS INSTITUTE OF TECHNOLOGY Simple Decisions if <condition>: <body> yes <condition>true? no <body> 8
Simple Decisions 8
上游通大￥ ParisTech SHANGHAI JIAO TONG UNIVERSITY INSTITUT DES SCIENCES ET TECHNOLOGIES PARIS INSTITUTE OF TECHNOLOGY Two-Way Decisions if <condition>: <statements 1> else: <statements 2> 10 yes condition statements 2 statements 1 9
Two-Way Decisions 9
上游充通大 ParisTech SHANGHAI JIAO TONG UNIVERSITY INSTITUT DES SCIENCES ET TECHNOLOGIES PARIS INSTITUTE OF TECHNOLOGY Examples printParity (x) no yes X%2==0 print x,"is odd" print x,"is even" def printparity(x): ifx号2==0： print x,"is even" else: print x,"is odd< printparity() 10
Examples 10 def printParity(x): if x%2 == 0: print x, "is even" else: print x, "is odd« printParity()