next alpha sequence value from var pointing to array

[jdmorgan]

Hello,

I am still fairly new to python, but find it to be a great scripting 
language.Here is my issue:


I am attempting to utilize a function to receive any sequence of letter 
characters and return to me the next value in alphabetic order e.g. send 
in "abc" get back "abd".I found a function on StackExchange (Rosenfield, 
A 1995) that seems to work well enough (I think):


/def next(s):/

/strip_zs = s.rstrip('z')/

/if strip_zs:/

/return strip_zs[:-1] + chr(ord(strip_zs[-1]) + 1) + 'a' * (len(s) - 
len(strip_zs))/


/else:/

/return 'a' * (len(s) + 1)/

I have found this function works well if I call it directly with a 
string enclosed in quotes:


returnValue = next("abc")

However, if I call the function with a variable populated from a value I 
obtain from an array[] it fails returning only ^K


Unfortunately, because I don't fully understand this next function I 
can't really interpret the error.Any help would be greatly appreciated.


Thanks ahead of time,

Derek

-- 
http://mail.python.org/mailman/listinfo/python-list

Re: next alpha sequence value from var pointing to array

[jdmorgan]

Hi Peter,

Thanks for you feedback. I have the next_alpha function you have 
provided.  But, am still getting the same result.
The actual value I am passing in is "btl".  But, as I mentioned I am 
getting it from an array value.  Here is my actual code.
I am reading a comma separated file, getting the last item and trying to 
get the next alpha.  Thanks again.



def getNRTLid(layerName):
lids_seen = []
lyrs_seen = []
last_lid = ""
f = open("NRTLayerLID.csv", "r");
for line in f:
sp = line.split(',')
lyrs_seen.append(sp[0])
lids_seen.append(sp[1])
f.close();
sorted_array = sorted(lids_seen)
sorted_array.reverse()
print "highest lid is %s" % sorted_array[0]
highest_lid = sorted_array[0]
test = highest_lid.lower()
nl = next_alpha(test)


Best,
Derek
--
http://mail.python.org/mailman/listinfo/python-list

Re: next alpha sequence value from var pointing to array

[jdmorgan]

Newline was the issue indeed.  Thanks for you help Peter.

Cheers,
Derek
--
http://mail.python.org/mailman/listinfo/python-list