學習索引和切片之後，我們開始學習更多關於清單和內建方法的知識。方法有
無回傳
回傳整數
回傳 str
對於交付清單的較小更改，內建功能本身就足夠了。但是當我們想要對列表進行更多操作時，就需要for循環、if循環。
例如，有一個清單 ['Pencil', 'Notebook', 'Marker', 'Highlighter', 'Glue Stick', 'Eraser', 'Laptop', 3]，其中只有字串需要轉換為大寫。這裡我們不能直接使用列表或字串方法。理想的邏輯是
- 我們必須逐一迭代列表
- 檢查項目是字串還是其他類型
- 相應地使用字串方法 upper() 和append()
所以這裡for循環，需要if,else條件
delivery_list= ['Pencil', 'Notebook', 'Marker', 'Highlighter', 'Glue Stick', 'Eraser', 'Laptop', 3]
upper_list = []
for item in delivery_list:
if type(item) == str:
upper_list.append(item.upper())
else:
upper_list.append(item)
print('Upper case list is:', upper_list)
Output:
Upper case list is: ['PENCIL', 'NOTEBOOK', 'MARKER', 'HIGHLIGHTER', 'GLUE STICK', 'ERASER', 'LAPTOP', 3]
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給的任務是多練習這些方法和邏輯。找到可用的邏輯或方法很有趣。
已解決詳情為
Tasks_list.py
#######################################################################################
#1. Create a list of five delivery items and print the third item in the list.
#eg: [“Notebook”, “Pencil”, “Eraser”, “Ruler”, “Marker”]
#######################################################################################
delivery_list = ['Notebook', 'Pencil', 'Eraser', 'Ruler', 'Marker']
print (f'\t1. Third item in the list{delivery_list} is: {delivery_list[2]}')
#######################################################################################
# 2.A new delivery item “Glue Stick” needs to be added to the list.
# Add it to the end of the list and print the updated list.
#######################################################################################
delivery_list.append('Glue Stick')
print('\t2. Updated delivery list is:', delivery_list)
#######################################################################################
# 3. Insert “Highlighter” between the second and third items and print the updated list.
#######################################################################################
delivery_list.insert(2, 'Highlighter')
print('\t3. Updated list by inserting Highlighter b/w 2nd &3rd:', delivery_list)
#######################################################################################
# 4. One delivery was canceled. Remove “Ruler” from the list and print the updated list.
#######################################################################################
delivery_list.remove('Ruler')
print('\t4. Updated list after removing Ruler is:', delivery_list)
#######################################################################################
# 5. The delivery man needs to deliver only the first three items.
# Print a sublist containing only these items.
#######################################################################################
sublist =[]
for item in delivery_list[:3]:
#sublist =sublist.append(item) #This is incorrect as sublist.append() returns None.
sublist.append(item)
print('\t5. Sublist of first three elements using loop:', sublist)
print('\t Sublist of first three elements using slicing:', delivery_list[:3])
#######################################################################################
# 6.The delivery man has finished his deliveries.
# Convert all item names to uppercase using a list comprehension and print the new list.
#######################################################################################
uppercase_list=[]
for item in delivery_list:
uppercase_list.append(item.upper())
print('\t6. Uppercase list of delivery items:', uppercase_list)
uppercase_list_lc = [item.upper() for item in delivery_list]
print('\t6. Uppercase list using list compre:', uppercase_list_lc)
#######################################################################################
# 7. Check if “Marker” is still in the list and print a message indicating whether it is found.
# 8. Print the number of delivery items in the list.
#######################################################################################
is_found= delivery_list.count('Marker')
if 'Marker' in delivery_list:
print(f'\t7. Marker is found {is_found} times')
else:
print(f'\t7. Marker is not found {is_found}')
print(f'\t8. Number of delivery item from {delivery_list} is: ', len(delivery_list))
#######################################################################################
# 9. Sort the list of items in alphabetical order and print the sorted list
# 10. The delivery man decides to reverse the order of his deliveries.
# Reverse the list and print it
#######################################################################################
delivery_list.sort()
print(f'\t9. Sorted delivery list is {delivery_list}')
delivery_list.reverse()
print(f'\t10. Reverse list of delivery list is {delivery_list}')
#######################################################################################
# 11. Create a list where each item is a list containing a delivery item and its delivery time.
# Print the first item and its time.
#######################################################################################
delivery_list_time = [['Letter', '10:00'], ['Parcel', '10:15'], ['Magazine', '10:45'], ['Newspaper', '11:00']]
print('\t11. First delivery item and time', delivery_list_time[0])
delivery_list = ['Pencil', 'Notebook', 'Marker', 'Highlighter', 'Glue Stick', 'Eraser', 'Laptop']
delivery_time = ['11:00','11:20','11:40','12:00','12:30','13:00', '13:30']
#Paring of two list using zip
paired_list=list(zip(delivery_list,delivery_time))
print('\tPaired list using zip:', paired_list[0:2])
#Combine corresponding item from multiple list using zip and for
item_time_list = [[item,time] for item, time in zip(delivery_list, delivery_time)]
print ('\tItem_time_list using list comprehension: ', item_time_list[0:1])
#######################################################################################
# 12. Count how many times “Ruler” appears in the list and print the count.
# 13. Find the index of “Pencil” in the list and print it.
# 14. Extend the list items with another list of new delivery items and print the updated list.
# 15. Clear the list of all delivery items and print the list.
# 16. Create a list with the item “Notebook” repeated three times and print the list.
# 17. Using a nested list comprehension, create a list of lists where each sublist contains an item
# and its length, then print the new list.
# 18. Filter the list to include only items that contain the letter “e” and print the filtered list.
# 19. Remove duplicate items from the list and print the list of unique items.
#######################################################################################
is_found= delivery_list.count('Ruler')
print('\t12. The count of Ruler in delivery list is:', is_found)
index_pencil = delivery_list.index('Pencil')
print(f'\t13. Index of Pencil in {delivery_list} is {index_pencil}')
small_list = ['Ink','']
delivery_list.extend(small_list)
print('\t14. Extend list by extend:', delivery_list)
item_time_list.clear()
print('\t15. Clearing the list using clear():', item_time_list)
Notebook_list = ['Notebook']*3
print('\t16. Notebook list is:', Notebook_list)
#Filter the list with e letter
delivery_list
new_delivery_list = []
for item in delivery_list:
if 'e' in item:
new_delivery_list.append(item)
print ('\t18. Filtered list with items containing e:', new_delivery_list)
new_list_compre = [item for item in delivery_list if 'e' in item]
print ('\t18. Filtered list by list comprehension:', new_list_compre)
#Remove duplicate items
delivery_list.extend(['Ink', 'Marker'])
print('\t ', delivery_list)
for item in delivery_list:
if delivery_list.count(item) > 1:
delivery_list.remove(item)
print('\t19. Duplicate remove list:',delivery_list)
print('\t19. Duplicate remove list:',list(set(delivery_list)))
#######################################################################################
# 17. Using a nested list comprehension, create a list of lists where each sublist contains an item
# and its length, then print the new list.
#######################################################################################
#without list comprehension
nested_list = []
for item in delivery_list:
nested_list.append([item, len(item)])
print('\t17. ', nested_list[-1:-6:-1])
#Using list comprehension printing nested list
nested_list = [[item,len(item)] for item in delivery_list]
print('\t17. Nested list with length:', nested_list[:5])
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答案：
PS C:\Projects\PythonSuresh> python Tasks_list.py
1. Third item in the list['Notebook', 'Pencil', 'Eraser', 'Ruler', 'Marker'] is: Eraser
2. Updated delivery list is: ['Notebook', 'Pencil', 'Eraser', 'Ruler', 'Marker', 'Glue Stick']
3. Updated list by inserting Highlighter b/w 2nd &3rd: ['Notebook', 'Pencil', 'Highlighter', 'Eraser', 'Ruler', 'Marker', 'Glue Stick']
4. Updated list after removing Ruler is: ['Notebook', 'Pencil', 'Highlighter', 'Eraser', 'Marker', 'Glue Stick']
5. Sublist of first three elements using loop: ['Notebook', 'Pencil', 'Highlighter']
Sublist of first three elements using slicing: ['Notebook', 'Pencil', 'Highlighter']
6. Uppercase list of delivery items: ['NOTEBOOK', 'PENCIL', 'HIGHLIGHTER', 'ERASER', 'MARKER', 'GLUE STICK']
6. Uppercase list using list compre: ['NOTEBOOK', 'PENCIL', 'HIGHLIGHTER', 'ERASER', 'MARKER', 'GLUE STICK']
7. Marker is found 1 times
8. Number of delivery item from ['Notebook', 'Pencil', 'Highlighter', 'Eraser', 'Marker', 'Glue Stick'] is: 6
9. Sorted delivery list is ['Eraser', 'Glue Stick', 'Highlighter', 'Marker', 'Notebook', 'Pencil']
10. Reverse list of delivery list is ['Pencil', 'Notebook', 'Marker', 'Highlighter', 'Glue Stick', 'Eraser']
11. First delivery item and time ['Letter', '10:00']
Paired list using zip: [('Pencil', '11:00'), ('Notebook', '11:20')]
Item_time_list using list comprehension: [['Pencil', '11:00']]
12. The count of Ruler in delivery list is: 0
13. Index of Pencil in ['Pencil', 'Notebook', 'Marker', 'Highlighter', 'Glue Stick', 'Eraser', 'Laptop'] is 0
14. Extend list by extend: ['Pencil', 'Notebook', 'Marker', 'Highlighter', 'Glue Stick', 'Eraser', 'Laptop', 'Ink', '']
15. Clearing the list using clear(): []
16. Notebook list is: ['Notebook', 'Notebook', 'Notebook']
18. Filtered list with items containing e: ['Pencil', 'Notebook', 'Marker', 'Highlighter', 'Glue Stick', 'Eraser']
18. Filtered list by list comprehension: ['Pencil', 'Notebook', 'Marker', 'Highlighter', 'Glue Stick', 'Eraser']
['Pencil', 'Notebook', 'Marker', 'Highlighter', 'Glue Stick', 'Eraser', 'Laptop', 'Ink', '', 'Ink', 'Marker']
19. Duplicate remove list: ['Pencil', 'Notebook', 'Highlighter', 'Glue Stick', 'Eraser', 'Laptop', '', 'Ink', 'Marker']
19. Duplicate remove list: ['', 'Ink', 'Pencil', 'Notebook', 'Marker', 'Eraser', 'Laptop', 'Highlighter', 'Glue Stick']
17. [['Marker', 6], ['Ink', 3], ['', 0], ['Laptop', 6], ['Eraser', 6]]
17. Nested list with length: [['Pencil', 6], ['Notebook', 8], ['Highlighter', 11], ['Glue Stick', 10], ['Eraser', 6]]
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