how to retrieve strings from within strings

[Yudesh]

Hi

I need to ask something

I am trying to retrieve a value from a string and I have noticed the following:

Scenario:
- I have retrieved lines from a file and need to read each line to retreive a certain string from the line i.e.
LINE = "THISISATEST"
I would need to retrieve the work TEST for processing.

I have noticed that when I declare string - and then parse for the value like string[8:4] it gives me a blank, but when I say string[8:len(string)], I get a value.

The problem comes in when I am trying to retrieve a value before the end of the string i.e. If I had to get the value ISA.

How do I do it, because using the string[0:0] format does not work - or does it?

Am I using it incorrectly?

Should I be using something like the find/ rfind command?

Thanks
Yudesh

[bgeddy]

You're using slicing incorrectly. The format is string[X:Y:Z] where X=start position (starts from 0), Y=non inclusive end position and Z=step.

So :
string="THISISATESTISNTIT"
string[7:11]="TEST

Check out slicing in the docs..

You could use :

if "TEST" in string:

to just test for the existence of "TEST" in the string.

[jlm699]

>>> srch = 'isa'
>>> st = 'thisisateststring'
>>> st[st.find(srch):st.find(srch)+len(srch)]
'isa'
>>>
 

Using a combination of find and the slicing will enable you to have a little more flexibility with your code

[Yudesh]

Thanks for the info guys - I will put it to good use