Slicing every element of a list

Gary Herron gherron at islandtraining.com
Tue Jul 12 21:35:51 CEST 2005


Alex Dempsey wrote:

>Recently I tried to slice every element of a list of strings. First I tried:
>
>f = open("export.xls", "r")
>lines = f.readlines()
>
>for line in lines:
>    line = line[1:-5]
>    line = line.split('\"\t\"')
>  
>
This, in fact, did do the operation you expected, but after creating the 
new value and assigning it to line, you promptly threw it away. (Because 
the loop then went back to the top and (re)assigned the next thing in 
lines to line wiping out your nicely sliced computation in lines.)  You 
need to *do* something with the value in line before you end the loop -- 
but what?

>This went without returning any errors, but nothing was sliced or
>split. Next I tried:
>
>for i in range(len(lines)):
>    lines[i] = lines[i][1:-5]
>    lines[i] = lines[i].split('\"\t\"')
>
>This of course worked, but why didn't the first one work. Further why
>didn't the first one return an error?
>  
>
Dr. Gary Herron
Digipen Institute of Technology





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