Question

如何在成本中添加2.50？

现在它只是将其打印为2.

cost = 0.00

r = open("toppings.txt")

bases = ["small","medium","large"]

toppings = ["Pepperoni","Chicken","Cajun Chicken","Mushrooms",
            "Red Onions","Sweetcorn","Ham","Cheese","Spicy Minced Beef",
            "Anchovies","Tuna","Peppers","Jalapenos","Green Chillies"] #0-13

def small():

    current = cost + 2.50

    print("Your current total cost is " + "£" + str(int(current)))

Answer 1

有两个问题：

在int(current)转换为int时，您会丢失小数位。
如果您总是想要两个小数位，则必须使用某种字符串格式。

我建议只使用带有“2”小数位的str.format（此处由.2f强制执行）：

'Your current total cost is £ {:.2f} '.format(current)

如果你正在处理类似“钱”的变量，你应该使用decimal.Decimal而不是浮点数，这样你就不需要处理浮点数的“不精确性”。

Answer 2

您正在将此浮动当前账单金额转换为此行中的int

print("Your current total cost is " + "£" + str(int(current)))

而是使用此命令打印您当前的账单金额。

print("Your current total cost is " + "£" + "{0:.2f}".format(round(current,2)))

输出

Your current total cost is £5.50

Answer 3

int将数字转换为整数。例如，int(2.1) = 2

你的最后一行应该只有str(current)。

print("Your current total cost is " + "£" + str(current))

添加带有2位小数的数字到变量（2.50）

3 个答案: