使用python中的函数计算销售税

Question

我无法在 Python 3.3.5 中运行该程序，并且不确定我做错了什么。该程序 就是要求用户输入当月的总销售额，然后计算并显示 以下，县销售金额（县销售税为 2.5%）和金额 州销售税（州销售税率为 0.05）和总销售税（县加州） 我已经复制并粘贴了到目前为止所做的事情。

# Show individually the 5 purchases amounts, compute the state and county sales
# tax on those combined  purchases and calculate the total of taxes
# and purchases
county_sales_tax =  .025 
state_sales_tax = .05

# Enter the purchase price
def main():
  purchase = float(input('Enter the price of the purchase: '))
  calculate_totals(purchase)

# Calculate the purchase price with the coounty and state sales tax
def calculate_totals(purchase):
  county_sales_tax = purchase * .025 
  state_sales_tax = purchase * .05
  total_sales_tax = county_sales_tax + state_sales_tax
  total_price = purchase + state_sales_tax + county_sales_tax


# display the amount of the purchases, county and state sales
# taxes, combined amount of the both taxes and total sale with taxes
def display_totals(purchase, state_sales_tax, county_sales_tax, total_taxes, total_price):
  print('The purchase price is $, ')
  print('The county_sales_tax is $', \
    format (county_sales_tax, '.2f'))
  print('The state_sales_tax is $', \
    format (state_sales_tax, '.2f'))
  print('The total_sales_tax is $:, ')
  print('The total_price is $:, ')

# Call the main function
main()

Answer 1

我修正了一些东西，我会尝试找出其中的一些错误。

def calculateStateTax(price):
    state_sales_tax = .05
    return price * state_sales_tax

def calculateCountyTax(price):
    county_sales_tax =  .025
    return price * county_sales_tax

def displayTotals(price):
    print('Original price', price)
    state_tax = calculateStateTax(price)
    print('State tax', state_tax)
    county_tax = calculateCountyTax(price)
    print('County tax', county_tax)
    print('Total', price + state_tax + county_tax)

def main():
    price = float(input('Enter the price of the purchase: '))
    displayTotals(price)

1. 缩进在 Python 中非常重要！缩进用于定义事物的范围，注意定义函数内的所有代码都是制表符（或4个空格）

2. 一般情况下，您可以使用函数输入参数和返回值来传递东西，而不是声明全局变量。

3. 注意displayTotals 函数调用其他函数，并通过return 从它们中获取值。这意味着displayTotals 不需要传入所有这些参数。

4. 通常最好只在它们需要存在的范围内定义常量（例如，state_sales_tax 不需要是全局的）。