python string manipulation, finding a substring within a string
This question already has an answer here:
You must use output[begin:end] , not output[begin, end] (that's just how the syntax for slicing ordinary strings/lists/etc works). So:
minusStuffBeforeReqPer = output[reqPerIndx:len(output)]
However, this is redundant. So you should instead probably do this:
minusStuffBeforeReqPer = output[reqPerIndx:]
By omitting the end part of the slice, the slice will go all the way to the end of output .
You get a error about accessing a tuple without the [0] because you have passed a tuple (namely (reqPerIndx, len(output)) to the slicing [...] ), and you get an error about int having no __getitem__ because when you write reqPerIndx[0] , you are trying to get the 0 th element of reqPerIndx , which is an integer, but there is of course no such thing as the "0th element of an integer", because integers do not have elements.
As @AshwiniChaudhary points out in the comments, str.find will return -1 if the substring is not found. If you are certain that the thing you're looking for will always be found somewhere in output , I suppose you don't need to handle the -1 case, but it might be a good idea to do so anyway.
reqPerIndx = output.find(reqPerStr)
if reqPerIndx != -1:
minusStuffBeforeReqPer = ...
# etc
else:
# handle this case separately
You might have better luck with regexes. I don't know what output looks like, so I sort of just guessed - you should adapt this to match whatever you have in output .
>>> import re
>>> re.findall(r'(?:Requests per second:)s*(d+)', "Requests: 24")
[]
>>> re.findall(r'(?:Requests per second:)s*(d+)', "Requests per second: 24")
['24']
You have the error on those two lines:
minusStuffBeforeReqPer = output[reqPerIndx[0], len(output)]
instanceTestObj.reqPerSec = minusStuffBeforeReqPer[semiColIndx+1, eolIndx]
You have to use the : to create a range. start:end .
You can omit the last parameter to get to the end or omit the first parameter to omit the begining. The parameters can be negative number too. Since find might return -1 you'll have to handle it differently because if the string isn't found, you'll end up with:
minusStuffBeforeReqPer = output[-1:]
Which is the last char in the string.
You should have code that looks like this:
#output contains the string reqPerStr.
reqPerStr = "Requests per second:"
reqPerIndx = output.find(reqPerStr)
if reqPerIndx != -1:
minusStuffBeforeReqPer = output[reqPerIndx[0]:]
eolIndx = minusStuffBeforeReqPer.find("n")
semiColIndx = minusStuffBeforeReqPer.find(":")
if eolIndx > semiColIndx >= 0:
instanceTestObj.reqPerSec = minusStuffBeforeReqPer[semiColIndx+1:eolIndx]
This is good but, you should definitely change the code with a regex. As I understand, you really want to match a string that starts with reqPerStr and ends with n and get everything that is in between : and n .
You could do that with such pattern:
"Requests per second:(.*)n"
You'll end up with:
import re
reqPerIndx = output.find(reqPerStr)
match = re.match("Requests per second:(.*)n", output)
if match:
instanceTestObj.reqPerSec = match.group(1)
If you want to find all matches, you can do that:
for match in re.finditer("Requests per second:(.*)", output)
instanceTestObj.reqPerSec = match.group(1)
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