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Regular expression for word with specific prefix/suffix

i want to match the word only if the word is surrounded with a maximum of 1 wild character on either side followed by space or nothing on either side. for example I want ring to match 'ring' , ' ring' , ' tring', 'ring ', ' ringt', '' ringt ', ' ring ', 'tringt ', 'tringt '
but not:
'ttring', 'ringttt', 'ttringtt'
so far I have:
[?\s\S]ring[?\s\S][?!\s]
any suggestions?

If i understand correctly, this should do:
(?:^|\s)\S?ring\S?(?:\s|$)
(?:^|\s) - this non-capturing group makes sure that the pattern is preceded by a whitespace or at the beginning
\S? matches zero or one non-whitespace character
ring matches literal ring
(?:\s|$) - the zero width positive lookahead makes sure the match is preceded by a space or is at the end
Example:
In [92]: l = ['ring ', ' ringt', ' ringt ', ' ring ', \
'tringt ', 'tringt ', 'ttring', 'ringttt', 'ttringtt']
In [93]: list(filter(lambda s: re.search(r'(?:^|\s)\S?ring\S?(?:\s|$)', s), l))
Out[93]: ['ring ', ' ringt', ' ringt ', ' ring ', 'tringt ', 'tringt ']

Why don't these variables output their values properly?

I am currently working in Python 3.5 and I'm having an issue with the variables in my dictionary. I have numbers 1-29 as keys, with letters as their pairs and for some reason none of the double digit numbers register as one number. For example, 11 would come out as 1 and 1 (F and F) instead of 11(I) or 13 as one and 3 (F and TH) instead of 13(EO). Is there a way to fix this so that I can get the values of the double digit numbers?
my code is here:
Dict = {'1':'F ', '2':'U ', '3':'TH ', '4':'O ', '5':'R ', '6':'CoK ', '7':'G ', '8':'W ', '9':'H ',
'10':'N ', '11':'I ', '12':'J ', '13':'EO ', '14':'P ', '15':'X ', '16':'SoZ ', '17':'T ',
'18':'B ', '19':'E ', '20':'M ', '21':'L ', '22':'NGING ',
'23':'OE ' , '24':'D ', '25':'A ', '26':'AE ', '27':'Y ', '28':'IAoIO ', '29':'EA '}
textIn = ' '
#I'm also not sure why this doesn't work to quit out
while textIn != 'Q':
textIn = input('Type in a sentence ("Q" to quit)\n>')
textOut = ''
for i in textIn:
if i in Dict:
textOut += Dict[i]
else:
print("Not here")
print(textOut)

Your for i in textIn: will loop over the individual characters in your input. So if you write 11, it will actually be a string '11', and for i in '11' will go over the '1''s separately:
>>> text = input()
13
>>> text
'13' # See, it's a string with the single-quote marks around it!
>>> for i in text:
... print(i)
...
1
3
>>> # As you see, it printed them separately.
You don't need the for loop at all, you can just use:
if textIn in Dict:
textOut += Dict[textIn]
Since your dict has the key '11', and your textIn is equal to '11'.
There is an other major issue in your code too; the textOut variable gets overwritten on every loop, so you lose everything you've done. You want to create it outside of the while loop:
textOut = ''
while textIn != 'Q':
textIn = input('Type in a sentence ("Q" to quit)\n>')
if textIn in Dict:
textOut += Dict[textIn]
else:
print("Not here")
print(textOut)

Going character by character in a string and swapping whitespaces with python

Okay so I have to switch ' ' to *s. I came up with the following
def characterSwitch(ch,ca1,ca2,start = 0, end = len(ch)):
while start < end:
if ch[start] == ca1:
ch[end] == ca2
start = start + 1
sentence = "Ceci est une toute petite phrase."
print characterSwitch(sentence, ' ', '*')
print characterSwitch(sentence, ' ', '*', 8, 12)
print characterSwitch(sentence, ' ', '*', 12)
print characterSwitch(sentence, ' ', '*', end = 12)
Assigning len(ch) doesn't seem to work and also I'm pretty sure this isn't the most efficient way of doing this. The following is the output I'm aiming for:
Ceci*est*une*toute*petite*phrase.
Ceci est*une*toute petite phrase.
Ceci est une*toute*petite*phrase.
Ceci*est*une*toute petite phrase.

Are you looking for replace() ?
sentence = "Ceci est une toute petite phrase."
sentence = sentence.replace(' ', '*')
print sentence
# Ceci*sest*sune*stoute*spetite*sphrase.
See a demo on ideone.com additionally.
For your second requirement (to replace only from the 8th to the 12th character), you could do:
sentence = sentence[8:12].replace(' ', '*')

Assuming you have to do it character by character you could do it this way:
sentence = "this is a sentence."
replaced = ""
for c in sentence:
if c == " ":
replaced += "*"
else:
replaced += c
print replaced

How to reduce whitespace in Python? [duplicate]

This question already has answers here:
Is there a simple way to remove multiple spaces in a string?
(27 answers)
Closed 6 years ago.
How do I reduce whitespace in Python from
test = ' Good ' to single whitespace test = ' Good '
I have tried define this function but when I try to test = reducing_white(test) it doesn't work at all, does it have to do with the function return or something?
counter = []
def reducing_white(txt):
counter = txt.count(' ')
while counter > 2:
txt = txt.replace(' ','',1)
counter = txt.count(' ')
return txt

Here is how I solved it:
def reduce_ws(txt):
ntxt = txt.strip()
return ' '+ ntxt + ' '
j = ' Hello World '
print(reduce_ws(j))
OUTPUT:
' Hello World '

You need to use regular expressions:
import re
re.sub(r'\s+', ' ', test)
>>>> ' Good '
test = ' Good Sh ow '
re.sub(r'\s+', ' ', test)
>>>> ' Good Sh ow '
r'\s+' matches all multiple whitespace characters, and replaces the entire sequence with a ' ' i.e. a single whitespace character.
This solution is fairly powerful and will work on any combination of multiple spaces.

concatenate print stmt inside and outside of for loop into a sentence in python

def PrintFruiteListSentence(list_of_fruits):
print 'You would like to eat',
for i, item in enumerate (list_of_fruits):
if i != (len(list_of_fruits) - 1):
print item, 'as fruit', i+2, 'and',
else:
print item, 'as fruit', i+2,
print 'in your diet'
o/p
You would like to eat apple as fruit 1 and orange as fruit 2 and banana as fruit 3 and grape as fruit 4 in your diet.
How can i get this sentence in a variable which i can pass to another function ???
I want to pass this sentence as input to another function.

just change your call to print instead to a concatenation into an actual string.
def PrintFruiteListSentence(list_of_fruits):
sentence = 'You would like to eat '
for i, item in enumerate (list_of_fruits):
if i != (len(list_of_fruits) - 1):
sentence += item + ' as fruit ' + str(i+2) + ' and '
else:
sentence += item + ' as fruit ' + str(i+2)
sentence += ' in your diet'
print sentence
you could also use a list comprehension instead of a for loop but this is just unnecessary:
Also note that if you want i to start at a specific number, you can pass an index into enumerate
>>> def PrintFruiteListSentence(list_of_fruits):
sentence = 'You would like to eat ' + ' and '.join(fruit + ' as fruit ' + str(index) for index,fruit in enumerate(list_of_fruits,1)) + ' in your diet'
print(sentence)
>>> PrintFruiteListSentence(['apple','orange','grapes'])
You would like to eat apple as fruit 1 and orange as fruit 2 and grapes as fruit 3 in your diet
EDIT: make sure to convert i+2 to str(i+2)

The following code works:
def func(fruits):
start = "You would like to eat "
for i, item in enumerate(fruits):
if i != (len(fruits) - 1):
start += item + ' as fruit ' + str(i+1) + ' and ' # note you mistake(i+1 and not i+2)
else:
start += item + ' as fruit ' + str(i+1) # see above comment note
start += ' in your diet'
return start
print (func(["apple", "banana", "grapes"]))
You can also try to run the above snippet here on repl.it

First, you need to make it a variable, like so:
def PrintFruiteListSentence(list_of_fruits):
myStr = 'You would like to eat ',
for i, item in enumerate (list_of_fruits):
if i != (len(list_of_fruits) - 1):
myStr += item + ' as fruit ' + str(i+2)+ ' and '
else:
myStr += item + ' as fruit ' + str(i+2)
myStr += ' in your diet'
return myStr
def otherFunction(inputString):
print(inputString)
otherFunction(PrintFruiteListSentence(['apple','banana']))#example
Also look at str.format(), which makes life much easier.
EDIT:
Here is an example to illustrate a simple usage of str.format(). It might not seem powerful in this case, but can be very helpful for complicated string manipulation, or where you need a specific floating point format.
def formatExample(list_of_fruits):
myStr="you would like to eat "
for i in enumerate(list_of_fruits,1):
myStr += '{1:} as fruit {0:d}'.format(*i)+' and '
return myStr[:-4]+"in your diet."
otherFunction(formatExample(['apple','banana']))#prints the same thing

Okay this question has been answered already. But here is another take where the str.join method takes the center stage it deserves. No concatenating strings with +. No if / else statements. No unnecessary variables. Easy to read and understand whats happening:
def PrintFruiteListSentence(fruits):
return ' '.join([
'You would like to eat',
' and '.join(
'{0} as fruit {1}'.format(f, c) for c, f in enumerate(fruits, 1)
),
'in your diet'
])