Python Regular expression Re/re learning notes and simple exercises

#., \w,\s,\d,,^,$
# *,+,?, {n},{n,},{n,m}

The # RE module is used for the operation of a Python regular expression.
#
Characters
#
# 　　. Match any character other than line break
# \w matches letters or numbers or underscores or kanji
# \s matches any whitespace character
# \d Matching numbers
# \b Matches the beginning or end of a word
# ^ matches the start of the string
# $ match End of string
#
Views
#
# * Repeat 0 or more times
# + Repeat one or more times
# 　　? Repeat 0 or one time
# {n} repeats n times
# {N,} repeats n or more times
# {N,m} repeats n to M times


Import re
# Match (pattern, string, flags=0)
# match the specified content from the starting position according to the model to the string to match the individual
# Regular Expressions
# to match the string
# flag bit, used to control how regular expressions are matched
# strings = Re.match (' \d+ ', ' 123df45 ')
# Print (strings)
# Print (Strings.group ())
# Print (strings.groups ())
# <_sre. Sre_match object; Span= (0, 3), match= ' 123 ' >
# 123
# ()



#根据模型去字符串中匹配指定内容, matching a single
# obj = Re.search (' \d+ ', ' u9f34k ')
# print (obj)
# Print (Obj.group ())
# <_sre. Sre_match object; Span= (1, 2), match= ' 9 ' >
# 9




# Group and Groups
# a = ' 123abc456 '
# Print (Re.search ("([0-9]*) ([a-z]*] ([0-9]*)", a). Group ())
# # 123abc456
# Print (Re.search ("([0-9]*) ([a-z]*) ([0-9]*)", a). Groups ())
# # (' 123 ', ' abc ', ' 456 ')
# Print (Re.search ("([0-9]*) ([a-z]*) ([0-9]*)", a). Group (0))
# # 123abc456
# Print (Re.search ("([0-9]*) ([a-z]*) ([0-9]*)", a). Group (1))
# # 123
# Print (Re.search ("([0-9]*) ([a-z]*) ([0-9]*)", a). Group (2))
# #abc
# Print (Re.search ("([0-9]*) ([a-z]*) ([0-9]*)", a). Group (3))
# #456


# FindAll (pattern, string, flags=0)
# Both of these methods are used to match single values, that is, only one of the strings can be matched, and if you want to match all eligible elements in a string, you need to use FindAll.
# a = ' 123abc567 '
# obj = Re.findall (' \d+ ', a)
# print (obj)
# print ()
# [' 123 ', ' 567 ']


# sub (pattern, REPL, String, count=0, flags=0)
# used to replace matching strings

# content = ' 123abc456 '
# new_content = re.sub (' \d+ ', ' SB ', content)
# # SBABCSB
# Print (new_content)
# new = Re.sub (' \d+ ', ' Xxoo ', content,3)
# Print (new)
# Xxooabcxxoo

Content = "' 1-2 * ((60-30+1* (9-2*5/3+7/3*99/4*2998+10*568/14))-( -4*3)/(16-3*2)) '"
# new_content = Re.split (' \* ', content)
# Print (new_content)
# # [' ' 1-2 ', ' ((60-30+1 ', ' (9-2 ', ' 5/3+7/3 ', ' 99/4 ', ' 2998+10 ', ' 568/14 ') ')-(-4 ', ' 3 ')/(16-3 ', ' 2 ') ' "]
# New_content2 = Re.split (' \* ', content,1)
# Print (New_content2)
# # ["' 1-2", "((60-30+1* (9-2*5/3+7/3*99/4*2998+10*568/14)-( -4*3)/(16-3*2)) ']
#
# New_content3 = Re.split (' \* ', content,3)
# Print (NEW_CONTENT3)
# # [' ' 1-2 ', ' ((60-30+1 ', ' (9-2 ', ' 5/3+7/3*99/4*2998+10*568/14 ')-( -4*3)/(16-3*2)) ']



# new_content = Re.split (' [\+\-\*\/]+ ', content)
# Print (new_content)
# [' ' 1 ', ' 2 ', ' ((60 ', ' 30 ', ' 1 ', ' (9 '), ' 2 ', ' 5 ', ' 3 ', ' 7 ', ' 3 ', ' 99 ', ' 4 ', ' 2998 ', ' 10 ', ' 568 ', ' 14 ') ', ' (', ' 4 ', ' 3 ') ' , ' (16 ', ' 3 ', ' 2) ')


# INPP = ' 1-2* ((60-30 + (-40-5) * (9-2*5/3 + 7/3*99/4*2998 +10 * 568/14))-( -4*3)/(16-3*2)) '
# INPP = re.sub (' \s* ', ' ', INPP)
# Print (INPP)
# # 1-2* ((60-30+ (-40-5) * (9-2*5/3+7/3*99/4*2998+10*568/14))-( -4*3)/(16-3*2))
#
# new_content = Re.split (' \ (([\+\-\*\/]?\d+[\+\-\*\/]?\d+) {1}\) ', INPP, 1)
# Print (new_content)

Python Regular expression Re/re learning notes and simple exercises