Python Tutorial 1 - PowerPoint PPT Presentation

1 / 75

About This Presentation

Title:

Python Tutorial 1

Description:

Python Tutorial 1 Yu-Tsao Hsing Laboratory for Reliable Computing Department of Electrical Engineering National Tsing Hua University Hsinchu, Taiwan – PowerPoint PPT presentation

Number of Views:1336

Avg rating:3.0/5.0

Slides: 76

Provided by: larcEeNt

Category:

more less

Transcript and Presenter's Notes

Title: Python Tutorial 1

1
Python Tutorial 1
??? Yu-Tsao Hsing

Laboratory for Reliable Computing
Department of Electrical Engineering
National Tsing Hua University
Hsinchu, Taiwan

2
Who am I ?

Yu-Tsao Hsing (???)
Email ythsing_at_larc.ee.nthu.edu.tw
http//larc.ee.nthu.edu.tw/ythsing
?? H01

3
Reference

Python ?? (Learning Python), Mark Lutz David
Ascber, OREILLY??, ISBN957-8247-35-4
??Python, ???, ????, ISBN957-466-280-2
Python ????, Guido van Rossum, ????http//larc.ee
.nthu.edu.tw/jcyeh/python/cdoc/tut/tut.html

4
Procedure

7/14 Python Tutorial (1) PM 7001000
1. Introduction
2. How to start ?
3. Embedded object types
7/21 Python Tutorial (2) PM 100400
4. Control structure
5. Function

5
Procedure (cont.)

7/28 Python Tutorial (3) PM 100400
6. Modules
7. Packages
8. Basic I/O
8/4 Python Tutorial (4) PM 100400
9. Exceptions
10. Classes

6
1. Introduction
7
Python

1991 ?? Guido van Rossum ?????????????
??? Zope ????? PythonLabs ?????
?? Python ? C ?????????

???? Scripting Language
? Java ?????? Jython ????,??? .NET ??

8
Why we need learning python?

????? (Object Oriented)
??????? (Interpreted, Interactive)
??? (Cross Platform)
???? (Easy Learning)
?????? (Clear Syntax and Structure)
????? (Extended and Embedded)
???? (Open Source)

9
Applications

Red Hat Linux ??????

10
Applications

???? mailman ??

11
Graphic User Interface
12
Resources Online

Python Language Website
http//www.python.org/
???????????...
Dive Into Python
http//diveintopython.net/
??????...
Zope Python User Group
http//zpug.org/
? WiKi ??????...
JPython Website
http//jpython.sourceforge.net/
Java ?????????...

Starship Python
http//starship.python.net/
??????...
Non-Programmers Tutorial For Python
http//www.honors.montana.edu/
jjc/easytut/easytut/easytut.html
Python FAQ
http//www.python.org/doc/FAQ.html
????????????...
ActiveState
http//www.activestate.com/
?? Python?Perl?Tcl ???...

13
2. How to Start
14
Some Rules

gtgtgt ???python?????
???Unix (or PC)???
python???????
?????
.py python??????
.pyc ???????python?????

15
Install

Unix
????
PC
http//www.python.org/ftp/python/2.3.4/Python-2.3.
4.exe
??????????
?????

16
Hello Python !

In Unix
python
gtgtgt print Hello python !
Hello python !
??Ctrl D????
In PC
??gtPython 2.3gt IDLE(python GUI)
gtgtgt print Hello python !
Hello python !
????????????

17
????python???

????????????LaRC.py
????????? python??
python LaRC.py
???(Unix?)?????????
!/usr/local/bin/python
???
chmod X LaRC.py
LaRC.py

18
??????

Python???????????
???dir()?????????????
gtgtgt x 1
gtgtgt y LaRC
gtgtgt dir( )
__builtins__, __doc__, __name__, x, y
gtgtgt dir(x)
??????????????

19
3. Embedded Object Type
20
Python?????

Python???????, ???????(Module), ??(Statement),
???(Object)
?????????
?????????
????????????
Everything in python is object !!

21
??????
???? ???? ??
?? Number 3.1415, 1234, 999L, 34j
?? String LaRC, NTHUs
?? List 1, 2, three, 4
?? Dictionary foodspam, tasteyum
Tuple Tuple (1, LaRC, 4, U)
?? File text open(eggs, r).read()
22
3.1 Number
23
Number-Introduction

??, and ??????
?C????, ????and?????????
???????

?? ??
1234, -24, 0 ????
999999999999L ???
1.23, 3.14e-10, 4E210, 4.0e210 ???
0177, 0x9ff 8???16????
34j, 3.04.0j, 3J ????
24
Number-??????

????????
????10???????
?????or??????????
??????
?? in Python long integer in C (32 bits)
??? in Python Double float in C
????L (or l), ?????????
16???8????
8?????0 ???????0, ????
16?????0x (or 0X)
??
??????j (or J)??
??????????

25
Number-????????(1/3)

???Python??????
???????????
??????????????????

??? ??
x or y, lambda args expression or?????, ????????
x and y and?????
not x ???????
lt, lt, gt, gt, , ltgt, ! is, is not in, not in ????? ???? ???????
26
Number-????????(2/3)
??? ??
x y or ?????
x y xor?????
x y and?????
x ltlt y, x gtgt y ?x??or????y???
x y, x - y ??, ??
x y, x / y, x y ??, ??, ????
-x, x, x ??, ??, ???????
xi, xij, x.y, x() ??, ??, ??????, ????
(), , , Tuple, ??, ??, ?????
27
Number-????????(3/3)

????
?????????????Q_Q
???()???
??????????????
?????????????
?????python?????????????
Python????????????????
?? lt ??? lt ??? lt ??
?????

28
Number-????(1/3)

???? ?????????
Python
gtgtgt a 3 ????lt????
gtgtgt b 4
gtgtgt b / 2 a ?? ((4/2)3)
5
gtgtgt b / (2.0 a) ?? (4/(2.03))
0.8
????
??2.0a, ??2.0, ?a?3gt3.0, ??5.0
??b/5.0, ??5.0, ?b?4gt4.0, ??0.8
If ?? 2 ???,?4/5???0

29
Number-????(2/3)

???? ??C??, ?????
For ????, ???????
gtgtgt x 1 001
gtgtgt x ltlt 2 100, ??????
4
gtgtgt x 2 011, 001 OR 010
3
??? ??????
??, ???, ???!!! (?????????)
gtgtgt 9999999999999999999999999999999 1
OverflowError integer literal too large
gtgtgt 9999999999999999999999999999999L 1
10000000000000000000000000000000

30
Number-????(3/3)

?? ????
gtgtgt 1j 1J
(-1 0j)
gtgtgt 2 1j 3
(23j)
gtgtgt (2 1j) 3
(63j)
?????
????math??????
gtgtgt import math
??C??includeltxxx.hgt
gtgtgt math.pi p
3.14159265359
gtgtgt abs(-42), 24, pow(2,4)
(42, 16, 16)

31
3.2 String
32
String-Introduction

?????
Immutable sequence ??????
???????????
???Lists????
???????
S1 ???
S2 spams ???
Block ?????
??? or ??? ?? ????? !!
?????????????????

33
String-???????

????
S1 S2 ??
S2 3 ????
for x in S2 ???????
m in S2 ????
?????????
S2 i ????
S2 i j ????
len(S2) ????
?????????
a s parrot dead ???????

34
String-????(1/2)

??????
gtgtgt len ( LaRC )
4
???????
gtgtgt LaRC EE
LaRCEE
?????? LaRC LaRC LaRC
gtgtgt LaRC 3
LaRCLaRCLaRC
????? !!
Python ??????
LaRC 3 ???????

35
String-????(2/2)

???????????????
gtgtgt mylab LaRC
gtgtgt R in mylab
1 means
true
gtgtgt for letter in mylab ???????
print letter
L
??print????
a
R
C
We will discuss the detail in next week

36
String-????????(1/3)

????C??, ?? 0 n-1
?????????? -n -1
Offset_p Offset_n n
gtgtgt mylab LaRC
gtgtgt mylab0, mylab-2 ??????
( L , R ) tuple
gtgtgt mylab13 ????
aR
????? (lower buond), (upper bound)
gtgtgtmylab1, mylab-1 ????
( aRC , LaR ) tuple

37
String-????????(2/3)
0
1
2
-2
-1
I
H
a
v
e
a
D
r
e
a
m

???? (Si)
??????????
???????????????
S-2 Slen(S)-2
???? (Sij)
????????????????
?????????0?len(S)
S-1 ??????????????????

38
String-????????(3/3)

???????1?????
cat echo.py
Import sys
??C??includeltxxx.hgt
Print sys.argv
Print sys.argv1
python echo.py a b c
echo.py , a , b , c
a , b , c
???????2?????????????
gtgtgt LaRC Lab for Reliable Computing\n
gtgtgt LaRC-1
Lab for Reliable Computing

39
String-????

?????!
gtgtgt mylab LaRC
gtgtgt mylab3 K
Traceback (most recent call last)
File ltpyshell9gt, line 1, in toplevel-
TypeError object doesnt support item assignment
???, ?? !!
???????????
gtgtgt mylab mylab-1 K!
gtgtgt mylab
LaRK!
gtgtgt mylab mylab4 is a bird
mylab-1
LaRK is a bird!

40
String-????(1/3)

gtgtgt That is d s! (1, bird )
??C?sprintf
That is 1 bird!
tuple
????? !!
??????

s ?? X 16????(??)
c ?? e ???????(??)
d 10???? E ???????(??)
i ?? f ???????
u ???? g ??????(??)
o 8???? G ??????(??)
x 16???? ????
41
String-????(2/3)

gtgtgt Mylab LaRC
gtgtgt I am in s now! Mylab
I am in LaRC now!
gtgtgt d s d ? (1, , 1)
1 1 ?
gtgtgt s - s - s (33, 3.1415926, 1, 2, 3)
33 3.1415926 1, 2, 3
s??????????????????
????????_at_O_at_
?????????????
gtgtgtI 3.1415926
gtgtgtI s I
gtgtgtI
3.1415926
??????????
???????????

42
????-???????

Python????????-string
gtgtgtimport string
gtgtgtS immediaTely
gtgtgtstring.upper(S)
?????
IMMEDIATELY
gtgtgtstring.lower(S)
?????
immediately
gtgtgtstring.find(S, mm)
??mm?string????
1
gtgtgtstring.atoi(151), 151
?????????????
( 151, 151 )
gtgtgt LaRC 151, string.atoi(151) 2
(LaRC151, 153)
gtgtgtstring.join(string.split(S, mm), ll)
?mm??, ??ll????
illediaTely
?????Python?Help?

43
String-????(3/3)

????
gtgtgtSARS We are the World
gtgtgtSARS
WearetheWorld
gtgtgtBig Oh, what is this ?
It is too big !!!
gtgtgtBig
Oh, what is this ? \n It is too big !!!

\newline ??? \n ????
\\ ??? \v ????
\ ??? \t ????
\ ??? \r ????
\a ?? \f ??
\b ???? \0XX 8????
\000 ??? \xXX 16????
44
???????-?????????

??python???????????, ?????????, ??????????,
???????????, ?????
????????????
Python?????????????????
?????????
?????????, ????, ??
?????key?????????
??, ??, ????????????_at_O_at_
???????, ?????????
???????
?????? (shared object reference)

45
3.3 List
46
List-Introduction

?????????
??????
???????(??, ??, ????)
????????
????????, ?????
?????, ????????gt?????,??
????, ??????
??????, ?????
????????????????
?????????
??????????????
????????????????
???????, ??????????????

47
List-??????

??????, ????????????
??? ?????????
?????C?????
????????
??????(??)
???, ?????????, ???????
?????????????
?????????????or????
?????????????
????copy????
????????????????

48
List-???????(1/2)

????
L1
???
L2 0, 1, 2, 3
4??????
L3 abc, def, ghi ????
len (L2)
??
L1 L2 ??
L2 3
????
For x in L2
????
3 in L2
????????
??????????
L2 i , L3 i j
?????
L2 i j
????

49
List-???????(2/2)

?????? lt??????
L2.append(4) ????
L2.sort( ) ??
L2.index(1) ??
L2.reverse( ) ??
del L2 k ????
L2 i j
L2 i 1 ?????
L2 i j 4, 5, 6 ????
range(4), xrange(0, 4) ??????? / tuple

50
List-????(1/2)

??
gtgtgt len( 1, 2, 3 )
3
??
gtgtgt 1, 2, 3 4, 5, 6
1, 2, 3, 4, 5, 6
????
gtgtgt Oh 4
Oh, Oh, Oh, Oh
?????
??????
gtgtgt for x in 1, 2
print x
1
2

51
List-????(2/2)

??, ??????
??????? ???????
??????? ???????
????????????????Q_Q
????
Ans. ?????
?????, ??
?????, ??list()
gtgtgt 1, 2 34 ?? 1,2
34
1, 2 34
gtgtgt 1, 2 list( 34 ) ?? 1, 2
3, 4
1, 2, 3, 4

52
List-??????????

??????????
gtgtgt mylab larc, Larc?, LaRC!
gtgtgt mylab 2
LaRC!
gtgtgt mylab -2
Larc?
gtgtgt mylab 1 ??????????
Larc?, LaRC!
???????, ??????????

53
List ??????(1/3)

???????????????
gtgtgt mylab larc, Larc?, LaRC!
gtgtgt mylab 1 is ????????
gtgtgt mylab
larc, is, LaRC!
?????? ???????????????
gtgtgt mylab 0 2 Im, a
gtgtgt mylab ?0,1??????
Im, a, LaRC!
??????????
gtgtgt mylab 1 2 student, in
gtgtgt mylab
Im, student, in, LaRC!

54
List-??????(2/3)

??????
????(qualification) (.)
?????????
????
?????, ??????????, ????
gtgtgt mylab.append( nthu )
gtgtgt mylab
Im, student, in, LaRC!, nthu
???? mylab mylab nthu
??? mylablen(mylab) nthu
??? mylablen(mylab) nthu
??????
???????, ???????????
??, ??????

55
List-??????(3/3)

??
??????, ????????
gtgtgt mylab.sort( )
??ASCII???
gtgtgt mylab
Im, LaRC!, in, nthu, student
??
gtgtgt del mylab-1 ??????
gtgtgt mylab
Im, LaRC!, in, nthu
gtgtgt del mylab-1 ??????
gtgtgt mylab
??mylab-1
nthu

56
3.4 Dictionary
57
Dictionary-Introduction

?key??, ?????
?????(associative array), ??(hash)
Key, ?????????(value)???????
?????????, ?????key not ???
??????, ????????
??????????????
Key??????????, ??????
??????value?, ?????
????, ???, ??????
??????, ???????? (????)
?????
????????(??), ?????????
??????, ???????????
???????(???)
????????????lt????????
???(Hash Table)

58
Dictionary-???????

????
D1
???
D2 LaRC1, NTHU2
?????????
D3 TWLaRC1, NTHU2 ????
D2NTHU, D3TWLaRC ?key??
D2.has_key(NTHU)
??????
D2.keys()
key??
D2.values()
?????????
len(D2)
????
??????
D2key new
??/??????
Del D2key
??

59
Dictionary-????

??key???
gtgtgt D2 LaRC1, NTHU2, TW3
gtgtgt D2NTHU
2
????????
gtgtgt len(D2)
3
Key?????
gtgtgt D2.hes_key(TW)
1
??key (??????)
?????????, ???
gtgtgt D2.keys()
LaRC, NTHU, TW

60
Dictionary-??????

????key????, ????key??????
?????
gtgtgt D2NTHU EE, CS
gtgtgt D2
LaRC1, NTHUEE, CS, TW3
?????
gtgtgt del D2TW
gtgtgt D2
LaRC1, NTHUEE, CS
?????
gtgtgt D28 floor
key???????
gtgtgt D2
8Floor, LaRC1, NTHUEE, CS

61
Dictionary-?????

gtgtgt table Python Guido van Rossum,
Perl Larry Wall,
Tcl John Ousterhout
gtgtgt language Python
gtgtgt creator tablelanguage
gtgtgt creator
Guido van Rossum
gtgtgt for lang in table.keys()
print lang, \t, tablelang
Perl Larry Wall
Tcl John Ousterhout
Python Guido van Rossum
????????, ??for??????keys()?????

62
3.5 Tuple, File
63
Tuple-Introduction

??????
??---????
???????????
????????or????
????????
????????
?????????????????
????????????????
???function?????
??????????

64
Tuple-??tuple??

( )
?tuple
T1 (0, )
1????tuple(??????)
T2 (0, 1, 2, 3) 4????tuple
T3 0, 1, 2, 3
4????tuple(?????)
T4 (abc, (def, ghi)) ??tuples
T1 i , T3 i j ?????
T1 ij , len(t1) ????, ??
T1 T2 ??
T2 3 ????
for x in T2 ????
3 in T2 ????

65
File-Introduction

???????
???????????
?????C???stdio?
Output open(/tree/temp.dat, w)
Input open(data.dat, r)
??
r????
w???????
a??????

66
File-????????

S input.read( ) ??????
S input.read(N) ??N????
S input.readline() ?????
L input.readlines() ????????????
Output.write(S) ???????
Output.writelines(L) ??????????
Output.close() ????
gtgtgt myfile open(myfile.txt, w) ?????
gtgtgt myfile.write(hello text file\n) ?????
gtgtgt myfile.close()
gtgtgt myfile open(myfile.txt, r) ?????
gtgtgt myfile.readline()
?????
hello text file\n
gtgtgt myfile.readline()
??? ????

67
3.6 ??
68
???????(1/3)

?????

??
???
??
??
??
???
????
???
??
??
??
???
??
??
Tuple
69
???????(2/3)

??????
Assignment manipulates references
x y does not make a copy of y
x y makes x reference the object y references
????, ????????
Example
gtgtgt a 1, 2, 3
gtgtgt b a
gtgtgt a.append(4)
gtgtgt print b
1, 2, 3, 4

70
???????1
a 1, 2, 3
b a
a
1
2
3
4
a.append(4)
b
71
???????2
a 1
a
1
b a
b
new int object created by add operator (11)
2
a
a a1
old reference deleted by assignment (a...)
1
b
72
???????(3/3)