Filtering a 2D array/list and replacing a value in python

Question

I want to replace a number in this 2d array if the username already exists.

[["bob man", "0"], ["bill kill", "5"], ["nick", "5"]]

For example, when I receive the username "bob man", with the new number 44. I want to search my array and check if this username exists, and replace the number. If it doesn't exist, I want to append it to the array.

[["bob man", "44"], ["bill kill", "5"], ["nick", "5"]]

Is there a better way of storing this? I am new to python, and simple stuff like this seems much more complex than in js etc. Objects?

Answer 1

You can use numpy structured array if you would like to keep the order:

a = np.array([("bob man", 0), ("bill kill", 5), ("nick", 5)], dtype=[('name', 'U10'), ('value', 'i4')])
new_entry = np.array([('bob man', 44)], dtype=[('name', 'U10'), ('value', 'i4')])

if new_entry['name'] in a['name']:
  a['value'][a['name']==new_entry['name']] = new_entry['value']
else:
  a = np.append(a, new_entry)

I expect it to be faster than dictionaries, specially if you want to add more than one entry, you can include them all in new_entry and change code a bit to check array-wise to be faster.