为什么我的python应用程序中的列表分配索引超出范围？

Question

So imagine I have this code in python:

import pickle
import numpy as np
import pandas as pd
x_u = []
load_model = open('dt.plk', 'rb')
dt = pickle.load(load_model)
cuantos = int(input('cuantas observaciones: '))
x_u[0] =pd.DataFrame(np.random.randint(341, size = 1))
x_u[1] =pd.DataFrame(np.random.randint(291, size = 1))
x_u[2] =pd.DataFrame(np.random.randint(150, size = 1))
x_u[3] =pd.DataFrame(np.random.randint(301, size = 1))
x_u[4] =pd.DataFrame(np.random.randint(341, size = 1))
x_u[5] =pd.DataFrame(np.random.randint(299, size = 1))
x_u[6] =pd.DataFrame(np.random.randint(150, size = 1))
x_u[7] =pd.DataFrame(np.random.randint(301, size = 1))
ps = dt.predict(x_u)
for d in x_u[0].tolist():
    if d == 0:
        print('Se queda')
    else:
        print('Se va')

When I run it I get this error. I've been modifying the index range with no success can you figure out what it is?

Traceback (most recent call last):
File "app.py", line 8, in <module>
x_u[0] =pd.DataFrame(np.random.randint(341, size = 1))
IndexError: list assignment index out of range

Answer 1

You're trying to assign a value to a list index that doesn't exist.

If you simply want to assign to those index values in order, you can use .append() :

list.append(x) Add an item to the end of the list. Equivalent to a[len(a):] = [x].

Thusly modified, your code might look like this:

import pickle
import numpy as np
import pandas as pd
x_u = []
load_model = open('dt.plk', 'rb')
dt = pickle.load(load_model)
cuantos = int(input('cuantas observaciones: '))
x_u.append(pd.DataFrame(np.random.randint(341, size = 1)))
x_u.append(pd.DataFrame(np.random.randint(291, size = 1)))
x_u.append(pd.DataFrame(np.random.randint(150, size = 1)))
x_u.append(pd.DataFrame(np.random.randint(301, size = 1)))
x_u.append(pd.DataFrame(np.random.randint(341, size = 1)))
x_u.append(pd.DataFrame(np.random.randint(299, size = 1)))
x_u.append(pd.DataFrame(np.random.randint(150, size = 1)))
x_u.append(pd.DataFrame(np.random.randint(301, size = 1)))
ps = dt.predict(x_u)
for d in x_u[0].tolist():
    if d == 0:
        print('Se queda')
    else:
        print('Se va')

Of course, without your input file, and desired input/output, it's hard to tell if this is what you desire.