练习26--恭喜你，来做个测试吧
引以为戒：
“有些程序员会宣称他们的代码很完美，这些人一般比较蠢，很少考虑别人的感受。好的程序员会像科学家一样，假设他们的代码总是存在一定概率是错的。好的程序员一般会在软件出现问题的情况下，用所有可能的方式排查自己会犯的错误，直到最后得出结论可能真的是其他人的代码出了问题。”
1 代码内容：
更改后的代码：
1 from sys import argv 2 # -*- coding:utf-8 -*- 3 4 5 6 print("How old are you?", end=' ') 7 age = input() 8 print("How tall are you?", end=' ') 9 height = input() 10 print("How much do you weigh?", end=' ') 11 weight = input() 12 13 print(f"So, you're {age} old, {height} tall and {weight} heavy.") 14 15 16 17 script, filename = argv 18 19 txt = open(filename) 20 21 print("Here's your file {filename}:") 22 print(txt.read()) 23 24 print("Type the filename again:") 25 file_again = input("> ") 26 27 txt_again = open(file_again) 28 29 print(txt_again.read()) 30 txt_again.close() 31 32 33 34 print('Let\'s practice everything.') 35 print('You\'d need to know \'bout escapes \ 36 with \\ that do \n newlines and \t tabs.') 37 38 poem = """ 39 \tThe lovely world 40 with logic so firmly planted 41 cannot discern \n the needs of love 42 nor comprehend passion from intuition 43 and requires an explanation 44 \n\t\twhere there is none. 45 """ 46 47 print("--------------") 48 print(poem) 49 print("--------------") 50 51 52 53 five = 10 - 2 + 3 - 6 54 print(f"This should be five: {five}") 55 56 57 58 def secret_formula(started): 59 jelly_beans = started * 500 60 jars = jelly_beans / 1000 61 crates = jars/100 62 return jelly_beans, jars, crates 63 64 start_point = 10000 65 beans, jars,crates= secret_formula(start_point) 66 67 # remember that this is another way to format a string 68 print("With a starting point of: {}".format(start_point)) 69 # it's just like with an f"" string 70 print(f"We'd have {beans} beans, {jars} jars, and {crates} crates.") 71 72 start_point = start_point / 10 73 74 print("We can also do that this way:") 75 formula = secret_formula(start_point) 76 # this is an easy way to apply a list to a format string 77 print("We'd have {} beans, {} jars, and {} crates.".format(*formula)) 78 79 80 81 people = 20 82 cats = 30 83 dogs = 15 84 85 if people < cats: 86 print ("Too many cats! The world is doomed!") 87 88 if people > cats: 89 print("Not many cats! The world is saved!") 90 91 if people < dogs: 92 print("The world is drooled on!") 93 94 if people > dogs: 95 print("The world is dry!") 96 97 dogs += 5 98 99 if people > dogs: 100 print("People are greater than or equal to dogs.") 101 102 if people < dogs: 103 print("People are less than or equal to dogs.") 104 105 if people == dogs: 106 print("People are dogs.")
我在改错过程中中没有检查到的地方是：定义函数过程和if条件判断后面的冒号、if语句的判断条件、自己改的过程中引入了拼写错误、有一个地方的拼写错误没有察觉到（start_point）以及height没有被定义，还是不够细心。
2 运行结果
1 PS E:\3_work\4_python\2_code_python\02_LearnPythonTheHardWay> python ex26.py test.txt 2 How old are you? 16 3 How tall are you? 162 4 How much do you weigh? 45 5 So, you're 16 old, 162 tall and 45 heavy. 6 Here's your file {filename}: 7 I 8 Love 9 You 10 11 Type the filename again: 12 > test.txt 13 I 14 Love 15 You 16 17 Let's practice everything. 18 You'd need to know 'bout escapes with \ that do 19 newlines and tabs. 20 -------------- 21 22 The lovely world 23 with logic so firmly planted 24 cannot discern 25 the needs of love 26 nor comprehend passion from intuition 27 and requires an explanation 28 29 where there is none. 30 31 -------------- 32 This should be five: 5 33 With a starting point of: 10000 34 We'd have 5000000 beans, 5000.0 jars, and 50.0 crates. 35 We can also do that this way: 36 We'd have 500000.0 beans, 500.0 jars, and 5.0 crates. 37 Too many cats! The world is doomed! 38 The world is dry! 39 People are dogs.
在运行过程中命令行参数没有给到test.txt文件也报错了。
