From 4d85ee545c85b3f20d2f73738ec13dd4166e15d3 Mon Sep 17 00:00:00 2001
From: Hui Lan
+ 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
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)
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
+@@ -932,6 +972,7 @@ t1d = {} or d = dict()'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