Kako obrezati bele prostore?

Ali obstaja funkcija Pythona, ki iz niza obreže bele prostore (presledke in tabulatorje)?

Primer: \t prime string\t → example string

martineau
Edited question Ndopoldan 28p10.11.20174tni 28trdopoldanni november 2017 в 2:20
Programiranje
python string whitespace strip trim
Npopoldan 38p26.7.20096tni 38trpopoldanni julij 2009 в 8:54
17 ogledi
Rešitev

Beli prostor na obeh straneh:

s = "  \t a string example\t  "
s = s.strip()

Beli prostor na desni strani:

s = s.rstrip()

Beli prostor na levi strani:

s = s.lstrip()

Kot je poudaril thedz, lahko kateri koli od teh funkcij posredujete argument za odstranitev poljubnih znakov, kot je ta:

s = s.strip(' \t\n\r')

To bo odstranilo vse znake presledka, \t, \n ali \r z leve, desne ali obeh strani niza.

Zgornji primeri odstranjujejo samo nize z leve in desne strani niza. Če želite znake odstraniti tudi s sredine niza, poskusite z re.sub:

import re
print re.sub('[\s+]', '', s)

To bi se moralo izpisati:

astringexample
Community
Edited answer Npopoldan 33p23.5.20171tni 33trpopoldanni maj 2017 в 12:10
Komentarji (11)

Za začetni in končni beli prostor:

s = '   foo    \t   '
print s.strip() # prints "foo"

V nasprotnem primeru deluje regularni izraz:

import re
pat = re.compile(r'\s+')
s = '  \t  foo   \t   bar \t  '
print pat.sub('', s) # prints "foobar"
blues
Edited answer Ndopoldan 38p23.10.20170tni 38trdopoldanni oktober 2017 в 11:58
Komentarji (3)
 
#how to trim a multi line string or a file

s=""" line one
\tline two\t
line three """

#line1 starts with a space, #2 starts and ends with a tab, #3 ends with a space.

s1=s.splitlines()
print s1
[' line one', '\tline two\t', 'line three ']

print [i.strip() for i in s1]
['line one', 'line two', 'line three']

#more details:

#we could also have used a forloop from the begining:
for line in s.splitlines():
    line=line.strip()
    process(line)

#we could also be reading a file line by line.. e.g. my_file=open(filename), or with open(filename) as myfile:
for line in my_file:
    line=line.strip()
    process(line)

#moot point: note splitlines() removed the newline characters, we can keep them by passing True:
#although split() will then remove them anyway..
s2=s.splitlines(True)
print s2
[' line one\n', '\tline two\t\n', 'line three ']
Komentarji (0)