函数调用不正确

Question

def main():

    def load():
        name=0
        count=0
        totalpr=0
        name=input("Enter stock name OR -999 to Quit: ")
        while name != '-999':
            count=count+1
            shares=int(input("Enter number of shares: "))
            pp=float(input("Enter purchase price: "))
            sp=float(input("Enter selling price: "))
            commission=float(input("Enter commission: "))
            name = input("Enter stock name OR -999 to Quit: ")

    def calc():
        amount_paid=shares*pp
        commission_paid_purchase=amount_paid*commission
        amount_sold=shares*sp
        commission_paid_sale=amount_sold*commission
        profit_loss=(amount_sold - commission_paid_sale) -(amount_paid + commission_paid_purchase)
        totalpr=totalpr+profit_loss

    def print():
        print("\nStock Name:", name)
        print("Amount paid for the stock:       $",      format(amount_paid, '10,.2f'))
        print("Commission paid on the purchase: $", format(commission_paid_purchase, '10,.2f'))
        print("Amount the stock sold for:       $", format(amount_sold, '10,.2f'))
        print("Commission paid on the sale:     $", format(commission_paid_sale, '10,.2f'))
        print("Profit (or loss if negative):    $", format(profit_loss, '10,.2f'))
        print("Total Profit is $", format(totalpr, '10,.2f'))
        return main()




load() #to input the values
calc()
print()

我不确定我做错了什么：

我应该将变量名放入def load():、def calc(): 和def print(): 吗？

当我现在运行它时，它说"load" 没有定义。我将如何定义load？就此而言，如果我没有定义 def calc(): 和 def print(): 我如何定义它们？

我确实在代码末尾正确地调用它们，按照我想要调用它们的顺序 - load、calc，然后是 print。

我的“return main()”是正确的做法吗？我不知道，我只是希望这段代码能够正常运行而不会出错，仅此而已。我的印象是我只是错过了一些东西。任何帮助，将不胜感激。

Answer 1

您在main() 的范围内定义load()。这意味着您不能在main()之外使用该功能。

简单的解决方案是你应该把你的函数定义放在main()的定义之外（顺便说一句，把它叫做print_stock info，print已经是一个函数了！）

您也不需要return main()。我不确定您要做什么，但根本没有必要。

Answer 2

哎呀。
你的第一个错误：在另一个函数中调用一个函数。也许你打算这样做

class Main:
    def load(self):
        #do a thing

那么你必须这样做

main = Main()
main.load()

您的第二个错误是定义了一个新的 print() 函数，该函数使用了 print 函数，因为它已经存在。重命名它，因为这会导致巨大的错误

Answer 3

这是一个最小的工作示例，用于说明如何解决您正在尝试做的事情。

# helper for interpreting input
import ast
#: initial starting values
thing, count, cost, total = 'Nothing', 0, 0, 0

# define all functions at module indentation
def get_user_input():
    global thing, count, cost  # write to the GLOBAL names thing, count and cost
    thing = input('What have you?')  # ask for a string
    count = ast.literal_eval(input('How much do you have?'))  # ask for a string and interpret it: "3.2" => float
    cost = ast.literal_eval(input('How much does each cost?'))

def compute():
    global total  # write to global name total
    total = count * cost  # can read from global names

def pretty_print():  # not named print! we still need print to print!
    print("You have", count, thing)
    print("At", cost, "each, that makes", total, "in total")

# call functions at module indentation
get_user_input()  # ducks, 3, 42
compute()
pretty_print()
# You have 3 ducks
# At 42 each, that makes 126 in total

要警告您的一件事：使用全局变量通常是个坏主意。对于一个小脚本来说这很好，但你已经搞砸了基础——全局变量很棘手，所以尽可能避免使用它们。如果只想运行这些命令，不要写成函数，直接执行。基本上，去掉 def ... 和 global ... 行并将所有内容放在同一个缩进上，然后删除最后三行。

如果你真的想存储和打印多个东西，你需要使用容器。只需在循环中分配一个值，例如thing = input('What have you?')，将保留最后输入的值。相反，您需要一个像list 这样的容器。然后你可以append给它附加值。

container = []  # [] is a list literal
for _ in range(3):  # non-infinite loop
    next_thing = ast.literal_eval(input('Place your order...\n'))
    container.append(next_thing)
print("You ordered", container)

Answer 4

def load():    
    global name
    global count
    global shares
    global pp
    global sp
    global commission
    name=input("Enter stock name OR -999 to Quit: ")
    count =0
    while name != '-999':
        count=count+1
        shares=int(input("Enter number of shares: "))
        pp=float(input("Enter purchase price: "))
        sp=float(input("Enter selling price: "))
        commission=float(input("Enter commission: "))
        calc()
        display()
        name=input("\nEnter stock name OR -999 to Quit: ")

def calc():
    global amount_paid
    global amount_sold
    global profit_loss
    global commission_paid_sale
    global commission_paid_purchase
    global totalpr
    totalpr=0
    amount_paid=shares*pp
    commission_paid_purchase=amount_paid*commission
    amount_sold=shares*sp
    commission_paid_sale=amount_sold*commission
    profit_loss=(amount_sold - commission_paid_sale) -(amount_paid + commission_paid_purchase)
    totalpr=totalpr+profit_loss

def display():
    print("\nStock Name:", name)
    print("Amount paid for the stock:       $",      format(amount_paid, '10,.2f'))
    print("Commission paid on the purchase: $", format(commission_paid_purchase, '10,.2f'))
    print("Amount the stock sold for:       $", format(amount_sold, '10,.2f'))
    print("Commission paid on the sale:     $", format(commission_paid_sale, '10,.2f'))
    print("Profit (or loss if negative):    $", format(profit_loss, '10,.2f'))

def main():
    load()


main()

print("\nTotal Profit is $", format(totalpr, '10,.2f'))