python - Finding index of the same elements in a list -

-

suppose have find each index of letter 'e' in word "internet":

letter = 'e' word = 'internet' idx = word.index(letter)

but code gives first index. how can find rest of them?

mark's answer better single letter. i'm adding in case real substring longer single character.

if want use str.index(), can take optional start position , raise valueerror if desired substring not found: 

>>> letter = 'e' >>> word = 'internet' >>> last_index = -1 >>> while true: ...     try: ...         last_index = word.index(letter, last_index + 1) ...         print last_index ...     except valueerror: ...         break ...  3 6

Comments

Post a Comment

Popular posts from this blog

How can I edit my VIM config so that Vim treats ".ejs" files the same as it currently treats my html files? -

-
what put in vim config? how change it? i want .html extension...because html... i think need au bufread,bufnewfile *.ejs setfiletype html au short autocmd docs it's idea put inside test if has("autocmd") au bufread,bufnewfile *.ejs setfiletype html endif to avoid error messages if ever use cut-down version of vim doesn't support feature. finally, if have default filetype rule like: au bufread,bufnewfile * setfiletype text then *.ejs rule must above it.
Read more

Python __call__ special method practical example -

-
i know __call__ method in class triggered when instance of class called. however, have no idea when can use special method, because 1 can create new method , perform same operation done in __call__ method , instead of calling instance, can call method. i appreciate if gives me practical usage of special method. django forms module uses __call__ method nicely implement consistent api form validation. can write own validator form in django function. def custom_validator(value): #your validation logic django has default built-in validators such email validators, url validators etc., broadly fall under umbrella of regex validators. implement these cleanly, django resorts callable classes (instead of functions). implements default regex validation logic in regexvalidator , extends these classes other validations. class regexvalidator(object): def __call__(self, value): # validation logic class urlvalidator(regexvalidator): def __call__(self, valu...
Read more