输出为blan

Question

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'))

def main():
    load()
    calc()
    print()

我想编写main（）函数来调用它上面的函数。你知道吗

但是，当我运行程序时，输出是空的-没有-没有给出错误来说明问题。你知道吗

我做错什么了？你知道吗

Answer 1

除了使用内置函数的问题外，还存在范围问题。因此，必须使每个函数中定义的变量global，以便可以在其他函数中对它们进行评估。你知道吗

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: "))
        name=input("Enter 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'))
    print("Total Profit is $", format(totalpr, '10,.2f'))

def main():
    load()
    calc()
    display()

main()

Answer 2

您没有调用main()，也没有更改print()函数名，这里我将其更改为fprint()

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 fprint():
    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'))

def main():
    load()
    calc()
    fprint()
main()

编辑：更改print（）的函数名

Answer 3

要将python模块作为程序运行，您应该像下面这样运行它。在您的程序中，main和其他函数一样，不会自动执行。你知道吗

if __name__ == '__main__':
    load()
    calc()
    print()

我们要做的是，检查模块名是否为__main__，并调用其他函数。__main__仅当我们将模块作为主程序运行时才设置。你知道吗