How to get a string after a specific substring

Question

How can I get a string after a specific substring  For example  I want to get the string after  quot world quot  in my string  quot hello python world   I m a beginner  quot   which in this case it is   I m a beginner

User · Answer

It s an old question but i faced a very same scenario  i need to split a string using as demiliter the word  low  the problem for me was that i have in the same string the word below and lower    I solved it using the re module this way  import re  string       below   as higher prices mean lower demand to be expected  Generally  a high reading is seen as negative  or bearish   while a low reading is seen as positive  or bullish  for the Korean Won     use re split with regex to match the exact word  stringafterword   re split    blow  b  string  -1  print stringafterword    reading is seen as positive  or bullish  for the Korean Won     the generic code is   re split    bTHE WORD YOU WANT  b  string  -1    Hope this can help someone

User · Answer

I m surprised nobody mentioned partition   def substring after s  delim       return s partition delim  2    IMHO  this solution is more readable than  arshajii s   Other than that  I think  arshajii s is the best for being the fastest -- it does not create any unnecessary copies substrings

User · Answer

s1    hello python world   i m a beginner   s2    world   print s1 s1 index s2    len s2      If you want to deal with the case where s2 is not present in s1  then use s1 find s2  as opposed to index  If the return value of that call is -1  then s2 is not in s1

User · Answer

In Python 3 9  a new removeprefix method is being added    gt  gt  gt   TestHook  removeprefix  Test    Hook   gt  gt  gt   BaseTestCase  removeprefix  Test    BaseTestCase     Documentation  https   docs python org 3 9 library stdtypes html str removeprefix Announcement  https   docs python org 3 9 whatsnew 3 9 html

User · Answer

Try this general approach   import re my string  hello python world   i m a beginner   p   re compile  world       print  p findall my string          i m a beginner

User · Answer

The easiest way is probably just to split on your target word  my string  hello python world   i m a beginner   print my string split  world  1  1     split takes the word or character  to split on and optionally a limit to the number of splits   In this example split on  world  and limit it to only one split

User · Answer

If you want to do this using regex  you could simply use a non-capturing group  to get the word  world  and then grab everything after  like so     world      The example string is tested here

User · Answer

You want to use str partition      gt  gt  gt  my string partition  world   2      i m a beginner     because this option is faster than the alternatives   Note that this produces an empty string if the delimiter is missing    gt  gt  gt  my string partition  Monty   2     delimiter missing      If you want to have the original string  then test if the second value returned from str partition   is non-empty   prefix  success  result   my string partition delimiter  if not success  result   prefix   You could also use str split   with a limit of 1    gt  gt  gt  my string split  world   1  -1      i m a beginner    gt  gt  gt  my string split  Monty   1  -1     delimiter missing  hello python world   i m a beginner     However  this option is slower  For a best-case scenario  str partition   is easily about 15  faster compared to str split                                     missing        first         lower         upper          last       str partition      2     3 745 usec    0 434 usec    1 533 usec    lt 3 543 usec gt    4 075 usec  str partition      and test    3 793 usec    0 445 usec    1 597 usec    3 208 usec    4 170 usec       str split      1  -1     lt 3 817 usec gt    lt 0 518 usec gt    lt 1 632 usec gt    3 191 usec    lt 4 173 usec gt                best vs worst          1 9          16 2           6 1           9 9           2 3    This shows timings per execution with inputs here the delimiter is either missing  worst-case scenario   placed first  best case scenario   or in the lower half  upper half or last position  The fastest time is marked with       and  lt     gt  marks the worst   The above table is produced by a comprehensive time trial for all three options  produced below  I ran the tests on Python 3 7 4 on a 2017 model 15  Macbook Pro with 2 9 GHz Intel Core i7 and 16 GB ram   This script generates random sentences with and without the randomly selected delimiter present  and if present  at different positions in the generated sentence  runs the tests in random order with repeats  producing the fairest results accounting for random OS events taking place during testing   and then prints a table of the results   import random from itertools import product from operator import itemgetter from pathlib import Path from timeit import Timer  setup    from   main   import sentence as s  delimiter as d  tests          str partition      2     r   s partition d  2         str partition      and test              prefix  success  result   s partition d  n           if not success  result   prefix              str split      1  -1     r   s split d  1  -1       placement    missing first lower upper last  split   delimiter count   3  wordfile   Path   usr dict words      Linux if not wordfile exists          macos     wordfile   Path   usr share dict words   words    w strip   for w in wordfile open     def gen sentence delimiter  where  missing   l 1000          Generate a random sentence of length l      The delimiter is incorporated according to the value of where        missing   no delimiter      first     delimiter is the first word      lower     delimiter is present in the first half      upper     delimiter is present in the second half      last      delimiter is the last word              possible    w for w in words if delimiter not in w      sentence   random choices possible  k l      half   l    2     if where     first             best case  at the start         sentence 0    delimiter     elif where     lower             lower half         sentence random randrange 1  half     delimiter     elif where     upper           sentence random randrange half  l     delimiter     elif where     last           sentence -1    delimiter       else  worst case  no delimiter      return     join sentence   delimiters   random choices words  k delimiter count  timings      sentences           where  delimiter  sentence      w  d  gen sentence d  w   for d  w in product delimiters  placement    test mix           label  test  where  delimiter sentence       t   s  for t  s in product tests items    sentences    random shuffle test mix   for i   label  test  where  delimiter  sentence  in enumerate test mix  1       print f  rRunning timed tests   i 2d   len test mix     end         t   Timer test  setup      number      t autorange       results   t repeat 5  number        best time for this specific random sentence and placement     timings setdefault          label           setdefault          where           append min dt   number for dt in results    print    scales     1 0   sec     0 001   msec     1e-06   usec     1e-09   nsec    width   max map len  timings   rows      bestrow   dict fromkeys placement   float  inf    None   worstrow   dict fromkeys placement   float  -inf    None    for row  label in enumerate tests       columns          worst   float  -inf       for p in placement          timing   min timings label  p           if timing  lt  bestrow p  0               bestrow p     timing  row          if timing  gt  worstrow p  0               worstrow p     timing  row          worst   max timing  worst          columns append timing       scale  unit   next  s  u  for s  u in scales if worst  gt   s      rows append           f  label  gt  width        f   c   scale  3f   unit    for c in columns          colwidth   max len c  for r in rows for c in r 1    print        width   1     p center colwidth  for p in placement   sep       for r  row in enumerate rows       for c  p in enumerate placement  1           if bestrow p  1     r              row c    f   row c  1 -1             elif worstrow p  1     r              row c    f  lt  row c  1 -1   gt       print  row  sep        percentages      for p in placement      best  worst   bestrow p  0   worstrow p  0      ratio     worst - best    worst      percentages append f  ratio  colwidth - 1  1       print    best vs worst   rjust width   1    percentages  sep

User · Answer

You can use the package called substring  Just install using the command pip install substring  You can get the substring by just mentioning the start and end characters indices  For example  import substring s   substring substringByChar  quot abcdefghijklmnop quot   startChar  quot d quot   endChar  quot n quot   print s   Output    s   defghijklmn

[python] How to get a string after a specific substring?

Examples related to python

Examples related to string

Examples related to substring