Question

为什么Python报告变量perimeter未定义？

#The first function will accept the length and width of a rectangle as its two parameters and return the rectangles perimeter
length=float(input("What is the length of your rectangle?"))
width=float(input("What is the width of your rectangle?"))
def rectanglePerimeter(length,width): #the parameter limits , it will accept the length and the width 
    perimeter= (2*length) + (2*width ) #here we implement the equation for the rectangles perimeter 
    return perimeter #return the result 
def rectangleArea(length,width):
    area= length*width 
    return area 
if perimeter> area:
    print ("the perimeter is larger than the area")
elif perimeter<area:
    print ("the area is larger than the perimeter")
    if perimeter == area:
        print ("the area and the perimeter are equal")

Answer 1

你还没有调用你的功能;你只定义了它们。要调用它们，您必须执行rectanglePerimeter(length, width)或rectangleArea(length, width)。

之类的操作

perimeter = rectanglePerimeter(length, width) # Where length and width are our inputs
area = rectangleArea(length, width) # Where once again length and width are our inputs

此外，您的if / elif语句似乎有点偏离：

if perimeter > area:
    print ("the perimeter is larger than the area")
elif perimeter < area:
    print ("the area is larger than the perimeter")
elif perimeter == area: # This should not be nested, and it should be another elif. Infact, you could probably put an else: here.
    print ("the area and the perimeter are equal")

Answer 2

2件事：

您应该将函数调用的结果存储到变量中。
你可以用else替换最后一个if语句（因为第三种情况只有在相等时才会发生）

#The first function will accept the length and width of a rectangle as its two parameters and return the rectangles perimeter
length=float(input("What is the length of your rectangle?"))
width=float(input("What is the width of your rectangle?"))

def rectanglePerimeter(length,width): #the parameter limits , it will accept the length and the width 
    perimeter= (2*length) + (2*width ) #here we implement the equation for the rectangles perimeter 
    return perimeter #return the result 

def rectangleArea(length,width):
    area= length*width 
    return area 

# need to call the functions, and store the results into variables here:
perimeter = rectanglePerimeter(length, width)
area = rectangleArea(length, width)

if perimeter> area:
    print ("the perimeter is larger than the area")
elif perimeter<area:
    print ("the area is larger than the perimeter")
else: # At this point, perimeter == area
    print ("the area and the perimeter are equal")

Answer 3

perimeter是一个局部变量，但您在函数外部使用它。事实上，你实际上从未调用任何函数。

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3 个答案: