How to replace a text in the nested list in Python-CodePudding

I am trying to replace an element in the nested list, but only the end part of the element

This is my nested list:

['715K', '2009-09-23', 'system.zip', ''],
 ['720M', '2019-09-23', 'sys2tem.zip~']]

And I want to replace "K" with "000" so it would look like this at the end:

 ['715000', '2009-09-23', 'system.zip', ''],
 ['720000', '2019-09-23', 'sys2tem.zip~']]

Separately it works, but I don"t know how to use index for the loop so that I could go through the nested list and change the text.

newList[0][0].replace("K", "000")

I have tried this approach but it did not work:

rules={"K":"000", "M":"000000", "G":"000000000"}
new=[]
for item in newList[i]:
    if item[i][0].endswith("K"):
        value=item[i][0].replace("K", "000")
        new.append(value)

I have got the error "'list' object has no attribute 'replace'"

CodePudding user response：

You could use replace() but there's potential for ambiguity so try this:

nested_list = [['715K', '2009-09-23', 'system.zip', ''],
               ['720M', '2019-09-23', 'sys2tem.zip~']]

for lst in nested_list:
    if lst[0][-1] == 'K':
        lst[0] = lst[0][:-1] '000'

print(nested_list)

Output:

[['715000', '2009-09-23', 'system.zip', ''], ['720M', '2019-09-23', 'sys2tem.zip~']]

CodePudding user response：

You got that error because you are performing replace on the list object. the below solution is based on the fact that, we are sure we just have list inside a list...

def f(el):
    rules = {"K" : "000", "M":"000000", "G":"000000000"}
    if el and el[-1] in ["K", "M", "G"]:
        return el.replace(el[-1], rules.get(el[-1]))
    return el

new_list = [list(map(f, ll)) for ll in l]
print(new_list)
# [['715000', '2009-09-23', 'system.zip', ''], ['720000000', '2019-09-23', 'sys2tem.zip~']]