使用循环在 python 中插入列表

Question

I'm trying to make a python program that I can insert a recipe, and I want to make a list of the ingredients. I know how to insert data as a certain spot in the list, using.insert, but when I use a for loop, I keep getting an error that says "TypeError: insert expected 2 arguments, got 1." I don't know what I'm doing wrong. Please help.

print("")
ingred=[]
measure=[]
n=0
i=0
for n in range(0,n+1):
    ingred[n]=ingred.insert(input("What is the ingredient?(type done to end ingrediants)"))
    n=n+1
    measure[i]=measure.insert(input("How much of the ingredient?"))
    i=i+1

Answer 1

Use the append function:

print("")
ingred=[]
measure=[]
n=10
for n in range(0,n+1):
    ingred.append(input("What is the ingredient?(type done to end ingrediants)"))
    measure.append(input("How much of the ingredient?"))

I don't really understand your n=n+1 code, so I removed it here - this should just run N times, which I set to be 10.

Answer 2

The insert() function takes two arguments, the element to insert and the index to insert it. To insert a recipe at the end of a list, use append() .

Answer 3

You don't add to a list by assigning to an index. You use the append() method.

And if you want to stop when they enter end , you need to assign the input to a variable so you can check it before appending to the list.

while True:
    name = input("What is the ingredient?(type done to end ingrediants)")
    if name == 'done':
        break
    ingred.append(name)
    measure.append(input("How much of the ingredient?"))