From 4d85ee545c85b3f20d2f73738ec13dd4166e15d3 Mon Sep 17 00:00:00 2001 From: Hui Lan Date: Sun, 31 Mar 2019 10:25:16 +0800 Subject: updated lecture notes --- LectureNotesOnPython.html | 107 ++++++++++++++++++++++++----------- LectureNotesOnPython.rst | 139 ++++++++++++++++++++++++---------------------- 2 files changed, 148 insertions(+), 98 deletions(-) diff --git a/LectureNotesOnPython.html b/LectureNotesOnPython.html index d8c31eb..3e55a72 100644 --- a/LectureNotesOnPython.html +++ b/LectureNotesOnPython.html @@ -818,12 +818,14 @@ in_both('apples', 'oranges')返回'aes'

+ 操作符用来连接， * 操作符用来重复。

列表的方法

+

append

extend

sort

-

t = ['d', 'c', 'e', 'b', 'a'] -t.sort() # 文t.sort()返回什么值？ -t

+

t = ['d', 'c', 'e', 'b', 'a']

+

t.sort() # 问t.sort()返回什么值？

+

t

+

sum - reduce方法，把几个值变成一个值

map方法，把几个值变成另外几个值

@@ -848,27 +850,56 @@ t

pop

-

t = ['a', 'b', 'c'] -x = t.pop(1) # pop可不带参数，不带参数返回哪个值？

-

t = ['a', 'b', 'c'] -del t[1]

-

t = ['a', 'b', 'c', 'd', 'e', 'f'] -del t[1:5]

-

t = ['a', 'b', 'c'] -t.remove('b')

-

list_of_characters = list('spam') -list_of_words = 'spam should be filtered'.split() -list_of_words = 'spam-should-be-filtered'.split('-')

+
+
+
t = ['a', 'b', 'c']
+
x = t.pop(1) # pop可不带参数，不带参数返回哪个值？
+
+
+

del

+
+
+
t = ['a', 'b', 'c']
+
del t[1]
+
+
+
t = ['a', 'b', 'c', 'd', 'e', 'f']
+
del t[1:5]
+
+
+

remove

+
+
+
t = ['a', 'b', 'c']
+
t.remove('b')
+
+
+

split

+
+
+
list_of_characters = list('spam')
+
list_of_words = 'spam should be filtered'.split()
+
list_of_words = 'spam-should-be-filtered'.split('-')
+
+

join方法

-

','.join(['1','2','3'])

-

a = 'banana' -b = 'banana' -a is b # a与b是不是指向同一个值 -a == b

-

a = [1, 2, 3] -b = [1, 2, 3] -a is b # not identical, a and b are not the same object -a == b # equivalent though they have the same values

+
+
+
','.join(['1','2','3'])
+
+
+
a = 'banana'
+
b = 'banana'
+
a is b # a与b是不是指向同一个值
+
a == b
+
+
+
a = [1, 2, 3]
+
b = [1, 2, 3]
+
a is b # not identical, a and b are not the same object
+
a == b # equivalent though they have the same values
+
+

别名（Aliasing）

a = [1, 2, 3] b = a @@ -880,6 +911,7 @@ error-prone（易错）

列表作为参数

+
def delete_head(t):
@@ -891,19 +923,26 @@ error-prone（易错）

delete_head(letters) # letters and t points to the same list object.
letters
+

注意区别 append 与 + 操作符

-

t1 = [1, 2] -t2 = t1.append(3) -t1 -[1, 2, 3] -t2

-

t3 = t1 + [4] -t3 -[1, 2, 3, 4] -t1 -[1, 2, 3]

+
+
+
t1 = [1, 2]
+
t2 = t1.append(3)
+
t1
+
[1, 2, 3]
+
t2
+
+
+
t3 = t1 + [4]
+
t3
+
[1, 2, 3, 4]
+
t1
+
[1, 2, 3]
+
+

区别如下两个函数:

@@ -918,6 +957,7 @@ t1

字典（Dictionary）

Mutable

超级有用

+
d = {} or d = dict()
@@ -932,6 +972,7 @@ t1
'warm' in d
'温' in d.values()
+

key

value

key-value pair (item)

diff --git a/LectureNotesOnPython.rst b/LectureNotesOnPython.rst index ae28903..52b2c2c 100644 --- a/LectureNotesOnPython.rst +++ b/LectureNotesOnPython.rst @@ -509,16 +509,18 @@ for x in []: 列表的方法 -append - -extend - -sort + append + + extend + + sort + + t = ['d', 'c', 'e', 'b', 'a'] -t = ['d', 'c', 'e', 'b', 'a'] -t.sort() # 文t.sort()返回什么值？ -t + t.sort() # 问t.sort()返回什么值？ + t + sum - reduce方法，把几个值变成一个值 map方法，把几个值变成另外几个值 @@ -542,41 +544,48 @@ filter方法，从几个值中选择符合条件的几个值 pop -t = ['a', 'b', 'c'] -x = t.pop(1) # pop可不带参数，不带参数返回哪个值？ - -t = ['a', 'b', 'c'] -del t[1] + | t = ['a', 'b', 'c'] + | x = t.pop(1) # pop可不带参数，不带参数返回哪个值？ + -t = ['a', 'b', 'c', 'd', 'e', 'f'] -del t[1:5] +del + | t = ['a', 'b', 'c'] + | del t[1] + + | t = ['a', 'b', 'c', 'd', 'e', 'f'] + | del t[1:5] + -t = ['a', 'b', 'c'] -t.remove('b') +remove + | t = ['a', 'b', 'c'] + | t.remove('b') + -list_of_characters = list('spam') -list_of_words = 'spam should be filtered'.split() -list_of_words = 'spam-should-be-filtered'.split('-') +split + | list_of_characters = list('spam') + | list_of_words = 'spam should be filtered'.split() + | list_of_words = 'spam-should-be-filtered'.split('-') + join方法 -','.join(['1','2','3']) - - -a = 'banana' -b = 'banana' -a is b # a与b是不是指向同一个值 -a == b - - -a = [1, 2, 3] -b = [1, 2, 3] -a is b # not identical, a and b are not the same object -a == b # equivalent though they have the same values - + | ','.join(['1','2','3']) + + + | a = 'banana' + | b = 'banana' + | a is b # a与b是不是指向同一个值 + | a == b + + + | a = [1, 2, 3] + | b = [1, 2, 3] + | a is b # not identical, a and b are not the same object + | a == b # equivalent though they have the same values + 别名（Aliasing） @@ -594,30 +603,30 @@ error-prone（易错） 列表作为参数 --------------------------------------------- -| def delete_head(t): -| del t[0] - -| letters = ['a', 'b', 'c'] -| delete_head(letters) # letters and t points to the same list object. -| letters - + | def delete_head(t): + | del t[0] + + | letters = ['a', 'b', 'c'] + | delete_head(letters) # letters and t points to the same list object. + | letters + 注意区别 ``append`` 与 ``+`` 操作符 ---------------------------------------------- -t1 = [1, 2] -t2 = t1.append(3) -t1 -[1, 2, 3] -t2 - - -t3 = t1 + [4] -t3 -[1, 2, 3, 4] -t1 -[1, 2, 3] - + | t1 = [1, 2] + | t2 = t1.append(3) + | t1 + | [1, 2, 3] + | t2 + + + | t3 = t1 + [4] + | t3 + | [1, 2, 3, 4] + | t1 + | [1, 2, 3] + 区别如下两个函数: @@ -638,17 +647,17 @@ Mutable 超级有用 -| d = {} or d = dict() - -| d = {'hot':'热', 'cool':'凉', 'cold':'冷'} -| d['warm'] = '温' -| d['warm'] -| d['freezing'] # KeyError -| len(d) - -| 'warm' in d -| '温' in d.values() - + | d = {} or d = dict() + + | d = {'hot':'热', 'cool':'凉', 'cold':'冷'} + | d['warm'] = '温' + | d['warm'] + | d['freezing'] # KeyError + | len(d) + + | 'warm' in d + | '温' in d.values() + key value -- cgit v1.2.1