PYTHON 101

Python Introduction at KSL UR

Transcript

1. PYTHON 101 @ KSL UR VICKY VERNANDO DASTA March 25th, 2017
2. About • student @ dept. of physics UR • founder of KSL UR • github.com/vickydasta • dasta.me
3. About Python (python.org) • guido van rosum (1997) • interpreted language • multipurpose • oop (everything is object) • easy to learn • dynamic typing • batteries included • case sensitive
5. Things we can build • machine learning (setruk) • computer vision • search engine (banyol) • web app (laporhoax.herokuapp.com) • web service (github.com/vickydasta/aha) • embedded system (micropython) • security/forensic tools (sqlmap, angr) • many more...
6. Python 101 an introduction to python programming language
7. Hello, Python!
8. Hello, World! open Python REPL, type: print “Hello, World!”
9. Data Structure • Integer • List • String • Float • Boolean • Dictionary • Tupple
10. Integer num = 12 num = num + 12 integer length only depends on memory size (as long as the memory can handle it, python still can do the job)
11. List sequence of data example: box = [1, 2, 3, 4] # create new list box[0] # get item on index 0 box.append(1) # add new item box.remove(1) # remove item on index 1
12. String sequence of character. example: greet = “hello world!” greet.upper() greet.count(‘o’)
13. Boolean logical data type example: True == False
14. Dictionary named list. JSON like data structure (key-value) example: user1 = {“name”: “ksl-ur”, “password”: “123”} user1[“name”] # get value with key “name” user1.keys() # get all keys
15. Tupple immutable list. once created, can’t: - add - remove example: box = (“apple”, “orange”) apple.append(“kiwi”) # error
16. We’re going to learn • Variables • Logical operation • Number operation • Looping • Function • Control Flow • Error handling • String operation • File I/O • Coding Style (pep8)
17. Variables pi = 3.14 greet = “hello world”
18. Logical Operation • 1 == 1 # equals • 1 > 2 # greater than • 1 < 2 # smaller than • 1 <= 2 # smaller and equals • 1 >= 2 # greater and equals • 1 & 1 # and • 1 | 2 # or
19. Number Operation • 1 + 1 # addition • 1-2 # reduction • 1 / 2 # division • 1*2 # multiply • 1 % 2 # modulo • 2 ** 2 # power
20. String Operation • we can do: - multiplication - addition example: “hello”+”world” “hello world”*5
21. Looping • while • for
22. for to iterate over an iterable object • for a in range(10): print a • for item in fruits: print item • for index, item in enumerate(fruit): ...print index, item
23. while logic based loop. only do the loop if the statement returns true. while 1==1: ...print ‘hello!’ else: ...print ‘hola!’
24. function method, routine, procedure example: def force(m): ...return m*9.8 print force(8)
25. control flow if 1 > 0: print “!!!” if 1 > 2: print “hola” else: print “holi” if 1 > 2: print “hola” elif 1 > 3: print “holu” else: print “holi”
26. error handling data = {“name”: “vicky”} try: ...name = data[“nam”] except KeyError as k: ...print “error!”
27. File I/O - open a text file, and print the content - open a text file, and write a content into it with open(‘filename’, ‘r’) as f: ...for text in f: …...print text with open(‘filename’, ‘w’) as f: ...f.write(‘hello world!’)
28. Demo/Question