ValueError和ZeroDivisionError

如何解决ValueError和ZeroDivisionError

我正在尝试执行（（x / y）+ z）的计算，并解决了2个错误：ValueError和ZeroDivisionError.

但是，我很难理解如何将这两个错误编码到我的程序中。我想我已经ValueError知道了，但是ZeroDivisionError没有。到目前为止，这就是我所拥有的。抱歉，它太乱了。...

user_input = (input("Enter three numbers separated by a space: ")).split()
x = int(user_input[0])
y = int(user_input[1])
z = int(user_input[2])
  
def calculate(x,y,z):
    '''calculate (x/y)+z'''
    c = ((x/y) + z) if y != 0 else print("Second input value cannot be 0")
    return c

try:
    input_values_str = str(user_input)
    c = ((x/y) + z)
    for val in input_values_str:
        if len(user_input) == 3:
            print("Correct number of values.")
        else:
            print("Incorrect number of values entered.")

except ValueError:
    print(user_input," is not valid input.")

except ZeroDivisionError:
    y = 0
    print("Second value cannot be 0")
print("Formula: ({}/{}) + {} = {}".format(x,z,calculate(x,z)))

解决方法

我根本不明白为什么您需要try / except / except块。您已经在y=0方法中检查calculate，并且已经知道输入有效，或者split并且强制转换int()失败。那里的for循环一遍又一遍地打印相同的输出字符串。如果将所有内容都排除掉，您的代码似乎可以正常工作

try:
    file_name = open('/tmp/data.txt','r')
except FileNotFoundError:
    print("File could not be found. Please check spelling of file name!")
    sys.exit()

#Read lines in file
Lines = file_name.read().splitlines()

user_input = (input("Enter three numbers separated by a space: ")).split()
x = int(user_input[0])
y = int(user_input[1])
z = int(user_input[2])

def calculate(x,y,z):
    '''calculate (x/y)+z'''
    c = ((x / y) + z) if y != 0 else print("Second input value cannot be 0")
    return c

print("Formula: ({}/{}) + {} = {}".format(x,z,calculate(x,z)))

,

您提出了一个异常以查看y == 0，但第一个值（x）也不能为0。并且您需要将2个if语句放在c = ...

之前

尝试一下：

user_input = (input("Enter three numbers separated by a space: ")).split()
x = int(user_input[0])
y = int(user_input[1])
z = int(user_input[2])

def calculate(x,z):
    '''calculate (x/y)+z'''
    if y == 0 or x == y:
        print("Invalid Input")
    else:
        c = ((x/y) + z)
        return c

try:
    input_values_str = str(user_input)
    c = ((x/y) + z)
    for val in input_values_str:
        if len(user_input) == 3:
            print("Correct number of values.")
        else:
            print("Incorrect number of values entered.")

except ValueError:
    print(user_input," is not valid input.")

except ZeroDivisionError:
    y = 0
    x = 0
    print("Second value cannot be 0. First Value cannot be 0")
    print("Formula: ({}/{}) + {} = {}".format(x,z)))

,

我只是对您的代码进行了调整以满足您的期望，并且易于理解。

user_input = (input("Enter three numbers separated by a space: ")).split()
x = int(user_input[0])
y = int(user_input[1])
z = int(user_input[2])

try:
    c = ((x/y) + z) if y != 0 else print("Second input value cannot be 0")
except ValueError:
    print(user_input," is not valid input.")
print("Formula: ({}/{}) + {} = {}".format(x,c))

,

恭喜您学习Python！我认为您的代码有些混乱。我将用一些评论发布您的版本，然后发布一个清理过的版本，我认为它可以更好地实现您的目标。希望这是指导性的。这样做有更优雅的方法，但是我正尽力保留您的结构。

您的代码：

user_input = (input("Enter three numbers separated by a space: ")).split()
x = int(user_input[0])
y = int(user_input[1])
z = int(user_input[2])

def calculate(x,z):
    c = ((x/y) + z) if y != 0 else print("Second input value cannot be 0")  #Why do you need a ZeroDivisonError check below when you check for Zero here?
return c

try:
    input_values_str = str(user_input) # why are you taking an input here? Did you take the input above? And why convert it back into a string?
    c = ((x/y) + z)
    for val in input_values_str: # Why are you iterating through string? You're basically checking 3 times if the length of your string is 3 characters
        if len(user_input) == 3:
            print("Correct number of values.")
        else:
            print("Incorrect number of values entered.")

except ValueError:
    print(user_input," is not valid input.")

except ZeroDivisionError:
    y = 0 # why set y back to zero in the event oa ZeroDivisonError? Won't that just create a ZeroDivison Error? Might make more sense to get a new input from the user
    print("Second value cannot be 0")
print("Formula: ({}/{}) + {} = {}".format(x,z))) # if the objective is to only print something,why not do it in the calculate function? Then we can contain your ZeroDivisionError in their and request a new y

我的代码：

def calculate(x,z):
    try:
        solution = (x/y) + z
        print(f"Formula: ({x}/{y}) + {z} = {solution}")

    except ZeroDivisionError:
        y = int(input("2nd value cannot be a Zero. Please input a new y value: "))
        calculate(x,z)

try:
    user_input = (input("Enter three numbers separated by a space: ")).split()

    while len(user_input) != 3:
        print("Incorrect number of values entered.")
        user_input = (input("Enter three numbers separated by a space: ")).split()

    x = int(user_input[0])
    y = int(user_input[1])
    z = int(user_input[2])

    calculate(x,z)

except ValueError:
    print(user_input," is not valid input.")