Develop Reference

Remove brackets and number inside from string Python

I've seen a lot of examples on how to remove brackets from a string in Python, but I've not seen any that allow me to remove the brackets and a number inside of the brackets from that string.
For example, suppose I've got a string such as "abc[1]". How can I remove the "[1]" from the string to return just "abc"?
I've tried the following:
stringTest = "abc[1]"
stringTestWithoutBrackets = str(stringTest).strip('[]')
but this only outputs the string without the final bracket
abc[1
I've also tried with a wildcard option:
stringTest = "abc[1]"
stringTestWithoutBrackets = str(stringTest).strip('[\w+\]')
but this also outputs the string without the final bracket
abc[1

You could use regular expressions for that, but I think the easiest way would be to use split:
>>> stringTest = "abc[1][2][3]"
>>> stringTest.split('[', maxsplit=1)[0]
'abc'

You can use regex but you need to use it with the re module:
re.sub(r'\[\d+\]', '', stringTest)
If the [<number>] part is always at the end of the string you can also strip via:
stringTest.rstrip('[0123456789]')
Though the latter version might strip beyond the [ if the previous character is in the strip list too. For example in "abc1[5]" the "1" would be stripped as well.

Assuming your string has the format "text[number]" and you only want to keep the "text", then you could do:
stringTest = "abc[1]"
bracketBegin = stringTest.find('[')
stringTestWithoutBrackets = stringTest[:bracketBegin]

How to copy changing substring in string?

How can I copy data from changing string?
I tried to slice, but length of slice is changing.
For example in one case I should copy number 128 from string '"edge_liked_by":{"count":128}', in another I should copy 15332 from "edge_liked_by":{"count":15332}

You could use a regular expression:
import re
string = '"edge_liked_by":{"count":15332}'
number = re.search(r'{"count":(\d*)}', string).group(1)

Really depends on the situation, however I find regular expressions to be useful.
To grab the numbers from the string without caring about their location, you would do as follows:
import re
def get_string(string):
return re.search(r'\d+', string).group(0)
>>> get_string('"edge_liked_by":{"count":128}')
'128'
To only get numbers from the *end of the string, you can use an anchor to ensure the result is pulled from the far end. The following example will grab any sequence of unbroken numbers that is both preceeded by a colon and ends within 5 characters of the end of the string:
import re
def get_string(string):
rval = None
string_match = re.search(r':(\d+).{0,5}$', string)
if string_match:
rval = string_match.group(1)
return rval
>>> get_string('"edge_liked_by":{"count":128}')
'128'
>>> get_string('"edge_liked_by":{"1321":1}')
'1'
In the above example, adding the colon will ensure that we only pick values and don't match keys such as the "1321" that I added in as a test.
If you just want anything after the last colon, but excluding the bracket, try combining split with slicing:
>>> '"edge_liked_by":{"count":128}'.split(':')[-1][0:-1]
'128'
Finally, considering this looks like a JSON object, you can add curly brackets to the string and treat it as such. Then it becomes a nested dict you can query:
>>> import json
>>> string = '"edge_liked_by":{"count":128}'
>>> string = '{' + string + '}'
>>> string = json.loads(string)
>>> string.get('edge_liked_by').get('count')
128
The first two will return a string and the final one returns a number due to being treated as a JSON object.

It looks like the type of string you are working with is read from JSON, maybe you are getting it as the output of some API you are working with?
If it is JSON, you've probably gone one step too far in atomizing it to a string like this. I'd work with the original output, if possible, if I were you.
If not, to make it more JSON like, I'd convert it to JSON by wrapping it in {}, and then working with the json.loads module.
import json
string = '"edge_liked_by":{"count":15332}'
string = "{"+string+"}"
json_obj = json.loads(string)
count = json_obj['edge_liked_by']['count']
count will have the desired output. I prefer this option to using regular expressions because you can rely on the structure of the data and reuse the code in case you wish to parse out other attributes, in a very intuitive way. With regular expressions, the code you use will change if the data are decimal, or negative, or contain non-numeric characters.

Does this help ?
a='"edge_liked_by":{"count":128}'
import re
b=re.findall(r'\d+', a)[0]
b
Out[16]: '128'

How to use regex to find the middle of a string

I'm trying to get certain results out of the response from Blogger. I wanna get my blog names. How would I go about something like that with Regex? I've tried Googling my issue but none of the answers helped me in my case unfortunately.
So my response looks something like this:
\\x22http://emyblog.blogspot.com/
So it's always starting with the \\x22http:// and ending with .blogspot.com/
I've tried the following re:
regEx = re.findall(b"""\x22http://(.*)\.blogspot\.com""", r)
But unfortunately it returned an empty list. Any idea's on how to solve this problem?
Thanks,

Use a raw string, otherwise \\x22 is interpreted as the character " instead of a literal string. Not sure that the re.findall method is the good method, re.search should suffice.
Assuming your byte-string is:
>>> r = rb'\\x22http://emyblog.blogspot.com/'
With byte-strings:
>>> res = re.search(rb'\\x22http://(.*)\.blogspot\.com/', r)
>>> res.group(1)
b'emyblog'
With normal strings:
>>> res = re.search(r'\\\\x22http://(.*)\.blogspot\.com/', r.decode('utf-8'))
>>> res.group(1)
'emyblog'

use r'' (string is taken as raw string literal) instead of b''
import re
pattern = re.compile(r'\x22http://(.*)\.blogspot\.com')
match = pattern.match('\x22http://emyblog.blogspot.com/')
match.group(1)
# 'emyblog'

This seems to be working!
import re
text = "\x22http://emyblog.blogspot.com/"
regex = re.compile('\x22http://(.*)\.blogspot\.com')
print regex.findall(text)

Python 2.7.3 BeautifulSoup- Remove u2019 and u2122 from string

I would like to modify the following piece of code to also replace u2019 and u2122 with a blank space, in addition to the comma it is already replacing with a blank space. How should I proceed? Thanks!
if(link != None):
items.put([link.text,link['href']])
f.write((link.text).encode("utf-8").replace(',','')+","+link['href'].encode("utf-8").split('&')[0]+newlinechar)

You need to use replace multiple times like so:
f.write((link.text).encode("utf-8").replace(',','').replace(u"\u2019", '').replace(u"\u2122", '')+","+link['href'].encode("utf-8").split('&')[0]+newlinechar)
This is inefficient however because a new String need to be recreated many times (Strings in Python are immutable). So consider using a regex instead to match and replace all 3 in one sweep.
>>> import re
>>> s = u"xdu\u2019sfs,"
>>> print s
xdu’sfs,
>>> print re.sub(u'[,\u2019\u2122]', '', s)
xdusfs

python: Match string using regular expression

I am learning regular expressions. Don't understand how to match the following pattern:
" myArray = ["Var1","Var2"]; "
Ideally I want to get the data in the array and to convert into python array

Are the array items guaranteed to be surrounded by double-quotes?
This is a quick and dirty method:
re.findall('"([^,]+)"', source)
where source is your string.
I didn't escape the double-quotes in the regex since you can also use single-quotes in Python.
This returns a list of each item surrounded by double quotes
so in your example: ['Var1', 'Var2']

Regular expression complexity differs much depending on variations of input. The easiest expressions that matches given string are:
>>> from re import search, findall
>>> s = ' myArray = ["Var1","Var2"]; '
>>> name, body = search(r'\s*(\w*)\s*=\s*\[(.*)\]', s).groups(0)
>>> contents = findall(r'"(\w*)"', body)
>>> name, contents
('myArray', ['Var1', 'Var2'])
"Converting" to python array can be done like this:
>>> globals().update({name: contents})
>>> myArray
['Var1', 'Var2']
Though it is actually a bad idea as it writes garbage in globals. Instead, try using separate dictionary, or something.

If you are interested in just getting the data in the array, you can skip using regex and use eval instead.
Consider this:
myArray = eval('["Var1","Var2"]')
If you must use the line you gave in the example, you can also use exec. However this command is somewhat dangerous and needs special care if used.

Without using an re you could use builtin string methods and literal_eval which given your example returns a usable list object:
from ast import literal_eval
text = ' myArray = ["Var1","Var2"]; '
name, arr_text = (el.strip('; ') for el in text.split('='))
arr = literal_eval(arr_text)
print name, arr
Then do what you want with name and arr...