Question

我正在创建一个程序，该程序将决定您是否应该升级计算机

#User inputs
CPU = int(raw_input("User, input the production year of your CPU: "))
GPU = int(raw_input("User, input the production year of your GPU, if  you have a dedicated GPU: "))
buyyear = int(raw_input("User, input the year that you bought or built your desktop/laptop: "))
date = int(raw_input("User, input current year: "))

#Calculations
CPUcalc = str(date - CPU)
GPUcalc = str(date - GPU)
avgcalc = str((GPUcalc + CPUcalc + buyyear)/3)

#Outputs
if date > avg_calc:
print ("Your computer is " + avgcalc + " years old. You might not need to upgrade your laptop/desktop, but if you think your laptop/desktop is slow, you may need to upgrade.")

elif date < avg_calc:
print ("Your computer is " + avgcalc + " years old. You may need to upgrade your laptop/desktop, but if you think your laptop/desktop is not slow, you my not need to upgrade.")

else:
print "ERROR: The program didn't meet the requirements for the program to calculate if you need to upgrade or not."
print "The equation is: ((current year - CPU year) + (current year - GPU year) + bought year) divide by 3) = x"
print "If 'x' is less than 4, you may not need to upgrade"
print "If 'x' is more than 4, you may need to upgrade"

期望：一个很长的描述，说您是否应该升级还是不可以。

结果：

Traceback (most recent call last):
File "F:\Free-Lance Coding\Computer Upgrading.py", line 10, in <module>
    avgcalc = str((GPUcalc + CPUcalc + buyyear)/3)
TypeError: cannot concatenate 'str' and 'int' objects

Answer 1

假设您以后想要打印CPUcalc，GPUcalc和avgcalc，则将值转换为字符串还为时过早。您正在尝试使用GPUcalc和CPUcalc进行计算，但是这些值实际上是不需要的时候是字符串。

仅将必须为字符串的值转换为字符串：

CPUcalc = date - CPU
GPUcalc = date - GPU
avgcalc = (GPUcalc + CPUcalc + buyyear) / 3

您还有一个错字，您同时引用了avgcalc和avg_calc。大概只有avgcalc存在：

if date > avgcalc:
    print ("Your computer is " + str(avgcalc) + " years old. You might not need to upgrade your laptop/desktop, but if you think your laptop/desktop is slow, you may need to upgrade.")

elif date < avgcalc:
    print ("Your computer is " + str(avgcalc) + " years old. You may need to upgrade your laptop/desktop, but if you think your laptop/desktop is not slow, you my not need to upgrade.")

else:
    print "ERROR: The program didn't meet the requirements for the program to calculate if you need to upgrade or not."
    print "The equation is: ((current year - CPU year) + (current year - GPU year) + bought year) divide by 3) = x"
    print "If 'x' is less than 4, you may not need to upgrade"
    print "If 'x' is more than 4, you may need to upgrade"

请注意，您不需要使用str()将值转换为字符串，仅在将非字符串对象与字符串连接时才需要。如果将值分别传递给语句，则可以print为您将值转换为字符串（此时，print在每个元素之间插入空格）：

if date > avgcalc:
    print "Your computer is", avgcalc, "years old. You might not need to upgrade your laptop/desktop, but if you think your laptop/desktop is slow, you may need to upgrade."

elif date < avgcalc:
    print "Your computer is", avgcalc, "years old. You may need to upgrade your laptop/desktop, but if you think your laptop/desktop is not slow, you my not need to upgrade."

else:
    # ...

您还可以在str.format() method中使用字符串格式：

if date > avgcalc:
    print "Your computer is {} years old. You might not need to upgrade your laptop/desktop, but if you think your laptop/desktop is slow, you may need to upgrade.".format(avgcalc)

elif date < avgcalc:
    print "Your computer is {} years old. You may need to upgrade your laptop/desktop, but if you think your laptop/desktop is not slow, you my not need to upgrade.".format(avgcalc)

else:
    # ...

{}占位符会将值转换为合适的字符串，或者您可以进一步配置应如何对待该值。

请注意，您的实际测试（date > avgcalc，date < avgcalc）和您在else分支中打印的文本彼此不一致，即您说要根据数字4。

您的计算也没有多大意义，为什么还要将购买计算机的年份与购买CPU和GPU以来的使用年数相加呢？您可能想在(date - buyyear)值中使用avgcalc。我还将在每个变量中使用术语age，以使值 mean

的含义更清楚。

CPU_age = date - CPU
GPU_age = date - GPU
computer_age = date - buyyear
avg_age = (CPU_age + GPU_age + computer_age) / 3

if avg_age > 4:
    # computer is old
else:
    # computer is still new enough

您的else:分支意义不大，因为只有date和avgcalc完全相等时才会发生。您可能想了解validating user input并在此处使用错误消息。

您也可以考虑使用Python获取当前年份，计算机通常已经知道日期。 Python具有datetime模块，其中datetime.date.today()为您获取今天的日期，并且生成的对象具有year属性：

import datetime

# ...

date = datetime.date.today().year

最后但并非最不重要的一点：如果您正在学习Python，则强烈建议您切换到Python3。Python2（现在使用的语言）将在1月终止使用2020年，little over 8 months from today。

Answer 2

您遇到以下问题：
-python 2中的打印语句print "Test"与python 3中的print("test")之间的区别
-if else语句后的缩进问题
-变量名不匹配avgcalc和avg_calc
-将avgcalc与字符串连接以打印
等

这是有效的代码，但实际上您需要了解python以及raw_input()和input()方法，print和print()在python版本方面的区别。 / p>

如果您使用的是Python 3：

#User inputs
CPU = int(input("User, input the production year of your CPU: "))
GPU = int(input("User, input the production year of your GPU, if  you have a dedicated GPU: "))
buyyear = int(input("User, input the year that you bought or built your desktop/laptop: "))
date = int(input("User, input current year: "))

#Calculations
CPUcalc = date - CPU
GPUcalc = date - GPU
avgcalc = (GPUcalc + CPUcalc + buyyear)/3

#Outputs
if date > avgcalc:
    print("Your computer is " + str(avgcalc) + " years old. You might not need to upgrade your laptop/desktop, but if you think your laptop/desktop is slow, you may need to upgrade.")

elif date < avgcalc:
    print("Your computer is " + str(avgcalc) + " years old. You may need to upgrade your laptop/desktop, but if you think your laptop/desktop is not slow, you my not need to upgrade.")

else:
    print("ERROR: The program didn't meet the requirements for the program to calculate if you need to upgrade or not.")
    print("The equation is: ((current year - CPU year) + (current year - GPU year) + bought year) divide by 3) = x")
    print("If 'x' is less than 4, you may not need to upgrade")
    print("If 'x' is more than 4, you may need to upgrade")

如果您使用的是python 2：

在上面的代码中，将input()替换为raw_input，并用print "your string"替换print（“ Your string”）。

Answer 3

尝试一下： avgcalc =（GPUcalc + CPUcalc +购买年份）/ 3

avgcalc = int（avgcalc）

发出串联“ str”和“ int”对象的问题

3 个答案: