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I want to replace a csv column with more than 8 hundred thousand rows but I can't do it with the following code:

import pandas as pd
import numpy as np
df = pd.read_csv('nameofdf.csv')
df

The nameofdf.csv has: enter image description here

I want to replace the numbers with strings so: 

new_df = df.replace([0, 1, 2, 3, 4, up to 8 hundred thousand], ['string1', 'string2', 'string3', 'string4', 'string5', up to string8hundred thousand])
new_df

After that, jupyter shows syntaxis error and I think it is because of the large lists...

Any idea about this or how to replace the csv properly?

Thanks!

Javulja
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    As per the linked duplicate, I recommend you convert your 2 lists to a dictionary, e.g. `d = dict(zip(list1, list2))`, and use `pd.Series.map`. If the list does not have full coverage, you can use `map` followed by `fillna`, which is still likely to be much faster than `replace`. – jpp May 19 '18 at 13:54
  • Thanks @jpp I am creating the lists but I have a problem with `list2 = ['string1', 'string2', 'string3', 'string4', 'string5', up to string8hundred thousand]`. Jupyter shows a syntaxis error and I do not why... (some strings appears in black colour). Thanks! – Javulja May 20 '18 at 10:12
  • Looks like you have a different problem. Unfortunately, there's not enough information yet to resolve the issue, but feel free to ask a separate question with a [mcve] and we can look to help. – jpp May 20 '18 at 10:29
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    I solved the problem, I had errors in the list, thanks! – Javulja May 22 '18 at 13:10

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