How do I replace the following using python
GSA*HC*11177*NYSfH-EfC*23130303*0313*1*R*033330103298
STEM*333*3001*0030303238
BHAT*3319*33*33377*23330706*031829*RTRCP
NUM4*41*2*My Break Room Place*****6*1133337
I want to replace the all character after first occurence of '*' . All characters must be replace except '*'
Example input:
NUM4*41*2*My Break Room Place*****6*1133337
example output:
NUM4*11*1*11 11111 1111 11111*****1*1111111
Fairly simple, use a callback to return group 1 (if matched) unaltered, otherwise
return replacement 1
Note - this also would work in multi-line strings.
If you need that, just add (?m) to the beginning of the regex. (?m)(?:(^[^*]*\*)|[^*\s])
You'd probably want to test the string for the * character first.
( ^ [^*]* \* ) # (1), BOS/BOL up to first *
| # or,
[^*\s] # Not a * nor whitespace
Python
import re
def repl(m):
if ( m.group(1) ) : return m.group(1)
return "1"
str = 'NUM4*41*2*My Break Room Place*****6*1133337'
if ( str.find('*') ) :
newstr = re.sub(r'(^[^*]*\*)|[^*\s]', repl, str)
print newstr
else :
print '* not found in string'
Output
NUM4*11*1*11 11111 1111 11111*****1*1111111
If you want to use regex, you can use this one: (?<=\*)[^\*]+ with re.sub
inputs = ['GSA*HC*11177*NYSfH-EfC*23130303*0313*1*R*033330103298',
'STEM*333*3001*0030303238',
'BHAT*3319*33*33377*23330706*031829*RTRCP',
'NUM4*41*2*My Break Room Place*****6*1133337']
outputs = [re.sub(r'(?<=\*)[^\*]+', '1', inputline) for inputline in inputs]
Regex explication here
Related
I'm trying to write a Ruby method that will return true only if the input is a valid phone number, which means, among other rules, it can have spaces and/or dashes between the digits, but not before or after the digits.
In a sense, I need a method that does the opposite of String#strip! (remove all spaces except leading and trailing spaces), plus the same for dashes.
I've tried using String#gsub!, but when I try to match a space or a dash between digits, then it replaces the digits as well as the space/dash.
Here's an example of the code I'm using to remove spaces. I figure once I know how to do that, it will be the same story with the dashes.
def valid_phone_number?(number)
phone_number_pattern = /^0[^0]\d{8}$/
# remove spaces
number.gsub!(/\d\s+\d/, "")
return number.match?(phone_number_pattern)
end
What happens is if I call the method with the following input:
valid_phone_number?(" 09 777 55 888 ")
I get false because line 5 transforms the number into " 0788 ", i.e. it gets rid of the digits around the spaces as well as the spaces. What I want it to do is just to get rid of the inner spaces, so as to produce " 0977755888 ".
I've tried
number.gsub!(/\d(\s+)\d/, "") and number.gsub!(/\d(\s+)\d/) { |match| "" } to no avail.
Thank you!!
If you want to return a boolean, you might for example use a pattern that accepts leading and trailing spaces, and matches 10 digits (as in your example data) where there can be optional spaces or hyphens in between.
^ *\d(?:[ -]?\d){9} *$
For example
def valid_phone_number?(number)
phone_number_pattern = /^ *\d(?:[ -]*\d){9} *$/
return number.match?(phone_number_pattern)
end
See a Ruby demo and a regex demo.
To remove spaces & hyphen inbetween digits, try:
(?:\d+|\G(?!^)\d+)\K[- ]+(?=\d)
See an online regex demo
(?: - Open non-capture group;
d+ - Match 1+ digits;
| - Or;
\G(?!^)\d+ - Assert position at end of previous match but (negate start-line) with following 1+ digits;
)\K - Close non-capture group and reset matching point;
[- ]+ - Match 1+ space/hyphen;
(?=\d) - Assert position is followed by digits.
p " 09 777 55 888 ".gsub(/(?:\d+|\G(?!^)\d+)\K[- ]+(?=\d)/, '')
Prints: " 0977755888 "
Using a very simple regex (/\d/ tests for a digit):
str = " 09 777 55 888 "
r = str.index(/\d/)..str.rindex(/\d/)
str[r] = str[r].delete(" -")
p str # => " 0977755888 "
Passing a block to gsub is an option, capture groups available as globals:
>> str = " 09 777 55 888 "
# simple, easy to understand
>> str.gsub(/(^\s+)([\d\s-]+?)(\s+$)/){ "#$1#{$2.delete('- ')}#$3" }
=> " 0977755888 "
# a different take on #steenslag's answer, to avoid using range.
>> s = str.dup; s[/^\s+([\d\s-]+?)\s+$/, 1] = s.delete("- "); s
=> " 0977755888 "
Benchmark, not that it matters that much:
n = 1_000_000
puts(Benchmark.bmbm do |x|
# just a match
x.report("match") { n.times {str.match(/^ *\d(?:[ -]*\d){9} *$/) } }
# use regex in []=
x.report("[//]=") { n.times {s = str.dup; s[/^\s+([\d\s-]+?)\s+$/, 1] = s.delete("- "); s } }
# use range in []=
x.report("[..]=") { n.times {s = str.dup; r = s.index(/\d/)..s.rindex(/\d/); s[r] = s[r].delete(" -"); s } }
# block in gsub
x.report("block") { n.times {str.gsub(/(^\s+)([\d\s-]+?)(\s+$)/){ "#$1#{$2.delete('- ')}#$3" }} }
# long regex
x.report("regex") { n.times {str.gsub(/(?:\d+|\G(?!^)\d+)\K[- ]+(?=\d)/, "")} }
end)
Rehearsal -----------------------------------------
match 0.997458 0.000004 0.997462 ( 0.998003)
[//]= 1.822698 0.003983 1.826681 ( 1.827574)
[..]= 3.095630 0.007955 3.103585 ( 3.105489)
block 3.515401 0.003982 3.519383 ( 3.521392)
regex 4.761748 0.007967 4.769715 ( 4.772972)
------------------------------- total: 14.216826sec
user system total real
match 1.031670 0.000000 1.031670 ( 1.032347)
[//]= 1.859028 0.000000 1.859028 ( 1.860013)
[..]= 3.074159 0.003978 3.078137 ( 3.079825)
block 3.751532 0.011982 3.763514 ( 3.765673)
regex 4.634857 0.003972 4.638829 ( 4.641259)
Is it possible to write a regex pattern to match abc where each letter is not literal but means that text like xyz (but not xxy) would be matched? I am able to get as far as (.)(?!\1) to match a in ab but then I am stumped.
After getting the answer below, I was able to write a routine to generate this pattern. Using raw re patterns is much faster than converting both the pattern and a text to canonical form and then comaring them.
def pat2re(p, know=None, wild=None):
"""return a compiled re pattern that will find pattern `p`
in which each different character should find a different
character in a string. Characters to be taken literally
or that can represent any character should be given as
`know` and `wild`, respectively.
EXAMPLES
========
Characters in the pattern denote different characters to
be matched; characters that are the same in the pattern
must be the same in the text:
>>> pat = pat2re('abba')
>>> assert pat.search('maccaw')
>>> assert not pat.search('busses')
The underlying pattern of the re object can be seen
with the pattern property:
>>> pat.pattern
'(.)(?!\\1)(.)\\2\\1'
If some characters are to be taken literally, list them
as known; do the same if some characters can stand for
any character (i.e. are wildcards):
>>> a_ = pat2re('ab', know='a')
>>> assert a_.search('ad') and not a_.search('bc')
>>> ab_ = pat2re('ab*', know='ab', wild='*')
>>> assert ab_.search('abc') and ab_.search('abd')
>>> assert not ab_.search('bad')
"""
import re
# make a canonical "hash" of the pattern
# with ints representing pattern elements that
# must be unique and strings for wild or known
# values
m = {}
j = 1
know = know or ''
wild = wild or ''
for c in p:
if c in know:
m[c] = '\.' if c == '.' else c
elif c in wild:
m[c] = '.'
elif c not in m:
m[c] = j
j += 1
assert j < 100
h = tuple(m[i] for i in p)
# build pattern
out = []
last = 0
for i in h:
if type(i) is int:
if i <= last:
out.append(r'\%s' % i)
else:
if last:
ors = '|'.join(r'\%s' % i for i in range(1, last + 1))
out.append('(?!%s)(.)' % ors)
else:
out.append('(.)')
last = i
else:
out.append(i)
return re.compile(''.join(out))
You may try:
^(.)(?!\1)(.)(?!\1|\2).$
Demo
Here is an explanation of the regex pattern:
^ from the start of the string
(.) match and capture any first character (no restrictions so far)
(?!\1) then assert that the second character is different from the first
(.) match and capture any (legitimate) second character
(?!\1|\2) then assert that the third character does not match first or second
. match any valid third character
$ end of string
I have a list of string i.e.
slist = ["-args", "-111111", "20-args", "20 - 20", "20-10", "args-deep"]
I want to remove the '-' from string where it is the first character and is followed by strings but not numbers or if before the '-' there is number/alphabet but after it is alphabets, then it should replace the '-' with space
So for the list slist I want the output as
["args", "-111111", "20 args", "20 - 20", "20-10", "args deep"]
I have tried
slist = ["-args", "-111111", "20-args", "20 - 20", "20-10", "args-deep"]
nlist = list()
for estr in slist:
nlist.append(re.sub("((^-[a-zA-Z])|([0-9]*-[a-zA-Z]))", "", estr))
print (nlist)
and i get the output
['rgs', '-111111', 'rgs', '20 - 20', '20-10', 'argseep']
You may use
nlist.append(re.sub(r"-(?=[a-zA-Z])", " ", estr).lstrip())
or
nlist.append(re.sub(r"-(?=[^\W\d_])", " ", estr).lstrip())
Result: ['args', '-111111', '20 args', '20 - 20', '20-10', 'args deep']
See the Python demo.
The -(?=[a-zA-Z]) pattern matches a hyphen before an ASCII letter (-(?=[^\W\d_]) matches a hyphen before any letter), and replaces the match with a space. Since - may be matched at the start of a string, the space may appear at that position, so .lstrip() is used to remove the space(s) there.
Here, we might just want to capture the first letter after a starting -, then replace it with that letter only, maybe with an i flag expression similar to:
^-([a-z])
DEMO
Test
# coding=utf8
# the above tag defines encoding for this document and is for Python 2.x compatibility
import re
regex = r"^-([a-z])"
test_str = ("-args\n"
"-111111\n"
"20-args\n"
"20 - 20\n"
"20-10\n"
"args-deep")
subst = "\\1"
# You can manually specify the number of replacements by changing the 4th argument
result = re.sub(regex, subst, test_str, 0, re.MULTILINE | re.IGNORECASE)
if result:
print (result)
# Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.
Demo
const regex = /^-([a-z])/gmi;
const str = `-args
-111111
20-args
20 - 20
20-10
args-deep`;
const subst = `$1`;
// The substituted value will be contained in the result variable
const result = str.replace(regex, subst);
console.log('Substitution result: ', result);
RegEx
If this expression wasn't desired, it can be modified or changed in regex101.com.
RegEx Circuit
jex.im visualizes regular expressions:
One option could be to do 2 times a replacement. First match the hyphen at the start when there are only alphabets following:
^-(?=[a-zA-Z]+$)
Regex demo
In the replacement use an empty string.
Then capture 1 or more times an alphabet or digit in group 1, match - followed by capturing 1+ times an alphabet in group 2.
^([a-zA-Z0-9]+)-([a-zA-Z]+)$
Regex demo
In the replacement use r"\1 \2"
For example
import re
regex1 = r"^-(?=[a-zA-Z]+$)"
regex2 = r"^([a-zA-Z0-9]+)-([a-zA-Z]+)$"
slist = ["-args", "-111111", "20-args", "20 - 20", "20-10", "args-deep"]
slist = list(map(lambda s: re.sub(regex2, r"\1 \2", re.sub(regex1, "", s)), slist))
print(slist)
Result
['args', '-111111', '20 args', '20 - 20', '20-10', 'args deep']
Python demo
I have a string with multiple commas and spaces as delimiters between words. Here are some examples:
ex #1: string = 'word1,,,,,,, word2,,,,,, word3,,,,,,'
ex #2: string = 'word1 word2 word3'
ex #3: string = 'word1,word2,word3,'
I want to use a regex to convert either of the above 3 examples to "word1, word2, word3" - (Note: no comma after the last word in the result).
I used the following code:
import re
input_col = 'word1 , word2 , word3, '
test_string = ''.join(input_col)
test_string = re.sub(r'[,\s]+', ' ', test_string)
test_string = re.sub(' +', ',', test_string)
print(test_string)
I get the output as "word1,word2,word3,". Whereas I actually want "word1, word2, word3". No comma after word3.
What kind of regex and re methods should I use to achieve this?
you can use the split to create an array and filter len < 1 array
import re
s='word1 , word2 , word3, '
r=re.split("[^a-zA-Z\d]+",s)
ans=','.join([ i for i in r if len(i) > 0 ])
How about adding the following sentence to the end your program:
re.sub(',+$','', test_string)
which can remove the comma at the end of string
One approach is to first split on an appropriate pattern, then join the resulting array by comma:
string = 'word1,,,,,,, word2,,,,,, word3,,,,,,'
parts = re.split(",*\s*", string)
sep = ','
output = re.sub(',$', '', sep.join(parts))
print(output
word1,word2,word3
Note that I make a final call to re.sub to remove a possible trailing comma.
You can simply use [ ]+ to detect extra spaces and ,\s*$ to detect the last comma. Then you can simply substitute the [ ]+,[ ]+ with , and the last comma with an empty string
import re
input_col = 'word1 , word2 , word3, '
test_string = re.sub('[ ]+,[ ]+', ', ', input_col) # remove extra space
test_string = re.sub(',\s*$', '', test_string) # remove last comma
print(test_string)
I have a string that looks like this:
my_str = "This sentence has a [b|bolded] word, and [b|another] one too!"
And I need it to be converted into this:
new_str = "This sentence has a <b>bolded</b> word, and <b>another</b> one too!"
Is it possible to use Python's string.replace or re.sub method to do this intelligently?
Just capture all the characters before | inside [] into a group . And the part after | into another group. Just call the captured groups through back-referencing in the replacement part to get the desired output.
Regex:
\[([^\[\]|]*)\|([^\[\]]*)\]
Replacemnet string:
<\1>\2</\1>
DEMO
>>> import re
>>> s = "This sentence has a [b|bolded] word, and [b|another] one too!"
>>> m = re.sub(r'\[([^\[\]|]*)\|([^\[\]]*)\]', r'<\1>\2</\1>', s)
>>> m
'This sentence has a <b>bolded</b> word, and <b>another</b> one too!'
Explanation...
Try this expression: [[]b[|](\w+)[]] shorter version can also be \[b\|(\w+)\]
Where the expression is searching for anything that starts with [b| captures what is between it and the closing ] using \w+ which means [a-zA-Z0-9_] to include a wider range of characters you can also use .*? instead of \w+ which will turn out in \[b\|(.*?)\]
Online Demo
Sample Demo:
import re
p = re.compile(ur'[[]b[|](\w+)[]]')
test_str = u"This sentence has a [b|bolded] word, and [b|another] one too!"
subst = u"<bold>$1</bold>"
result = re.sub(p, subst, test_str)
Output:
This sentence has a <bold>bolded</bold> word, and <bold>another</bold> one too!
Just for reference, in case you don't want two problems:
Quick answer to your particular problem:
my_str = "This sentence has a [b|bolded] word, and [b|another] one too!"
print my_str.replace("[b|", "<b>").replace("]", "</b>")
# output:
# This sentence has a <b>bolded</b> word, and <b>another</b> one too!
This has the flaw that it will replace all ] to </b> regardless whether it is appropriate or not. So you might want to consider the following:
Generalize and wrap it in a function
def replace_stuff(s, char):
begin = s.find("[{}|".format(char))
while begin != -1:
end = s.find("]", begin)
s = s[:begin] + s[begin:end+1].replace("[{}|".format(char),
"<{}>".format(char)).replace("]", "</{}>".format(char)) + s[end+1:]
begin = s.find("[{}|".format(char))
return s
For example
s = "Don't forget to [b|initialize] [code|void toUpper(char const *s)]."
print replace_stuff(s, "code")
# output:
# "Don't forget to [b|initialize] <code>void toUpper(char const *s)</code>."