Re: [Python-ideas] string method count()

2018-05-07 Thread Neil Girdhar
Regular expressions are not just "an order of magnitude better"—they're asymptotically faster. See https://en.wikipedia.org/wiki/Knuth%E2%80%93Morris%E2%80%93Pratt_algorithm for a non-regular-expression algorithm. On Thursday, April 26, 2018 at 5:45:20 AM UTC-4, Jacco van Dorp wrote: > > or bu

Re: [Python-ideas] string method count()

2018-04-26 Thread Wes Turner
If this was for a school assignment, I'd probably go to edit distance and fuzzy string match next: https://en.wikipedia.org/wiki/Edit_distance https://en.wikipedia.org/wiki/String-to-string_correction_problem - https://pypi.org/search/?q=Levenshtein - https://pypi.org/project/textdistance/ As a

Re: [Python-ideas] string method count()

2018-04-26 Thread Julia Kim
There are two ‘AA’ in ‘AAA’, one starting from 0 and the other starting from 1. If ‘AA’ starting from 0 is deleted and inserted with ‘BANAN’, ‘AAA’ becomes ‘BANANA ‘. If ‘AA’ starting from 1 is deleted and inserted with ‘PPLE’, ‘AAA’ becomes ‘APPLE’. Depending on which one is chosen, ‘AAA’ can

Re: [Python-ideas] string method count()

2018-04-26 Thread Jacco van Dorp
or build it yourself... def str_count(string, sub): c = 0 for c in range(len(string)-len(sub)): if string[c:].startswith(sub): c += 1 return c (probably some optimizations possible...) Or in one line with a generator expression: def str_count(string, sub): return sum(string[c:]

Re: [Python-ideas] string method count()

2018-04-26 Thread Wes Turner
On Wednesday, April 25, 2018, Steven D'Aprano wrote: > On Wed, Apr 25, 2018 at 11:22:24AM -0700, Julia Kim wrote: > > Hi, > > > > There’s an error with the string method count(). > > > > x = ‘AAA’ > > y = ‘AA’ > > print(x.count(y)) > > > > The output is 1, instead of 2. > > Are you proposing that

Re: [Python-ideas] string method count()

2018-04-25 Thread Steven D'Aprano
On Wed, Apr 25, 2018 at 11:22:24AM -0700, Julia Kim wrote: > Hi, > > There’s an error with the string method count(). > > x = ‘AAA’ > y = ‘AA’ > print(x.count(y)) > > The output is 1, instead of 2. Are you proposing that there ought to be a version of count that looks for *overlapping* substri

Re: [Python-ideas] string method count()

2018-04-25 Thread Alexandre Brault
str.count counts non-overlapping instances of the substring. After counting the first 'AA', there is only one A left, so that isn't a second instance of 'AA' On 2018-04-25 02:22 PM, Julia Kim wrote: > Hi, > > There’s an error with the string method count(). > > x = ‘AAA’ > y = ‘AA’ > print(x.coun

Re: [Python-ideas] string method count()

2018-04-25 Thread João Santos
Hi, >From https://docs.python.org/3/library/stdtypes.html#str.count: str.count(*sub*[, *start*[, *end*]]) Return the number of *non-overlapping* occurrences of substring *sub* in the range [*start*, *end*]. Optional arguments *start* and *end* are interpreted as in slice notation. Best regards, J

[Python-ideas] string method count()

2018-04-25 Thread Julia Kim
Hi, There’s an error with the string method count(). x = ‘AAA’ y = ‘AA’ print(x.count(y)) The output is 1, instead of 2. I write programs on SoloLearn mobile app. Warm regards, Julia Kim ___ Python-ideas mailing list Python-ideas@python.org https