AttributeError numpy ndarray object has no attribute append

Question

Hi Guys,

I am trying to append new  dataset in my array using append function, but It is showing me the error.

AttributeError: 'numpy.ndarray' object has no attribute 'append' 

How can I solve this error?

Comments

Thank you. Your answer helped me to solve this error well.

Answer 1

Hi@akhtar,

If you trying to append data in your array, then you can use the below steps.

import numpy as np
arr = np.array([1,1,2])
arr1 = np.append(arr,4)
arr1
array([1, 1, 2, 4])

Answer 2

Use numpy. append() to append an array to an empty array

1. empty_array = np. array([])
2. to_append = np. array([1, 2, 3])
3. combined_array = np. append(empty_array, to_append) append `to_append` to `empty_array`

Answer 3

for root, dirs, files in os.walk(directory):
    for file in files:
        floc = file
        im = Image.open(str(directory) + '\\' + floc)
        pix = np.array(im.getdata())
        pixels.append(pix)
        labels.append(1)   # append(i)???

So far ok. But you want to leave pixels as a list until you are done with the iteration.

pixels = np.array(pixels)
labels = np.array(labels)

You had this indention right in your other question.

Iterating, collecting values in a list, and then at the end joining things into a bigger array is the right way. To make things clear I often prefer to use notation like:

alist = []
for ..
    alist.append(...)
arr = np.array(alist)

If names indicate something about the nature of the object I'm less likely to get errors like yours.

I don't understand what you are trying to do with traindata. I doubt if you need to build it during the loop. pixels and labels have the basic information.

That

traindata = np.array([traindata[i][i],traindata[1]], dtype=object)

comes from the previous question. I'm not sure you understand that answer.

traindata = []
traindata.append(pixels)
traindata.append(labels)

if done outside the loop is just

traindata = [pixels, labels]

labels is a 1d array, a bunch of 1s (or [0,1,2,3...] if my guess is right). pixels is a higher dimension array. What is its shape?

Stop right there. There's no point in turning that list into an array. You can save the list with pickle.