Given a string, I have to reverse every word, but keeping them in their places.
I tried:
def backward_string_by_word(text):
for word in text.split():
text = text.replace(word, word[::-1])
return text
But if I have the string Ciao oaiC, when it try to reverse the second word, it's identical to the first after beeing already reversed, so it replaces it again. How can I avoid this?
You can use join in one line plus generator expression:
text = "test abc 123"
text_reversed_words = " ".join(word[::-1] for word in text.split())
s.replace(x, y) is not the correct method to use here:
It does two things:
find x in s
replace it with y
But you do not really find anything here, since you already have the word you want to replace. The problem with that is that it starts searching for x from the beginning at the string each time, not at the position you are currently at, so it finds the word you have already replaced, not the one you want to replace next.
The simplest solution is to collect the reversed words in a list, and then build a new string out of this list by concatenating all reversed words. You can concatenate a list of strings and separate them with spaces by using ' '.join().
def backward_string_by_word(text):
reversed_words = []
for word in text.split():
reversed_words.append(word[::-1])
return ' '.join(reversed_words)
If you have understood this, you can also write it more concisely by skipping the intermediate list with a generator expression:
def backward_string_by_word(text):
return ' '.join(word[::-1] for word in text.split())
Splitting a string converts it to a list. You can just reassign each value of that list to the reverse of that item. See below:
text = "The cat tac in the hat"
def backwards(text):
split_word = text.split()
for i in range(len(split_word)):
split_word[i] = split_word[i][::-1]
return ' '.join(split_word)
print(backwards(text))
Related
For instance I have a string that needs a certain keyword removed from a string so lets say may key word iswhatthemomooofun and I want to delete the word moo from it, I have tried using the remove function but it only removes "moo" one time, but now my string is whatthemoofun and I can seem to remove it is there anyway I can do that?
You can use the replace in built function
def str_manipulate(word, key):
while key in word:
word = word.replace(key, '')
return word
Have you tried using a while loop? You could loop through it until it doesn't find your keyword anymore then break out.
Edit
Cause answer could be improved by an example, take a look at the general approach it deals with:
Example
s = 'whatthemomooofun'
while 'moo' in s:
s= s.replace('moo','')
print(s)
Output
whatthefun
original_string = "!(Hell#o)"
characters_to_remove = "!()#"
new_string = original_string
for character in characters_to_remove:
new_string = new_string.replace(character, "")
print(new_string)
OUTPUT
Hello
I want to convert all the titlecase words (words starting with uppercase character and having rest of the characters as lowercase) in the string to the lowercase characters. For example, if my initial string is:
text = " ALL people ARE Great"
I want my resultant string to be:
"ALL people ARE great"
I tried the following but it did not work
text = text.split()
for i in text:
if i in [word for word in a if not word.islower() and not word.isupper()]:
text[i]= text[i].lower()
I also checked related question Check if string is upper, lower, or mixed case in Python.. I want to iterate over my dataframe and for each word that meet this criteria.
You could define your transform function
def transform(s):
if len(s) == 1 and s.isupper():
return s.lower()
if s[0].isupper() and s[1:].islower():
return s.lower()
return s
text = " ALL people ARE Great"
final_text = " ".join([transform(word) for word in text.split()])
You can use str.istitle() to check whether your word represents the titlecased string, i.e. whether first character of the word is uppercase and rest are lowercase.
For getting your desired result, you need to:
Convert your string to list of words using str.split()
Do the transformation you need using str.istitle() and str.lower() (I am using list comprehension for iterating the list and for generating a new list of words in desired format)
Join back the list to strings using str.join() as:
For example:
>>> text = " ALL people ARE Great"
>>> ' '.join([word.lower() if word.istitle() else word for word in text.split()])
'ALL people ARE great'
How is one of the following versions different from the other?
The following code returns the first letter of a word from string capitalize:
s = ' '.join(i[0].upper() + i[1:] for i in s.split())
The following code prints only the last word with every character separated by space:
for i in s.split():
s=' '.join(i[0].upper()+i[1:]
print s
For completeness and for people who find this question via a search engine, the proper way to capitalize the first letter of every word in a string is to use the title method.
>>> capitalize_me = 'hello stackoverlow, how are you?'
>>> capitalize_me.title()
'Hello Stackoverlow, How Are You?'
for i in s.split():`
At this point i is a word.
s = ' '.join(i[0].upper() + i[1:])
Here, i[0] is the first character of the string, and i[1:] is the rest of the string. This, therefore, is a shortcut for s = ' '.join(capitalized_s). The str.join() method takes as its argument a single iterable. In this case, the iterable is a string, but that makes no difference. For something such as ' '.join("this"), str.join() iterates through each element of the iterable (each character of the string) and puts a space between each one. Result: t h i s There is, however, an easier way to do what you want: s = s.title()
def make_new_words(start_word):
"""create new words from given start word and returns new words"""
new_words=[]
for letter in start_word:
pass
#for letter in alphabet:
#do something to change letters
#new_words.append(new_word)
I have a three letter word input for example car which is the start word.
I then have to create new word by replacing one letter at a time with every letter from the alphabet. Using my example car I want to create the words, aar, bar, car, dar, ear,..., zar. Then create the words car, cbr, ccr, cdr, cer,..., czr. Finally caa, cab, cac, cad, cae,..., caz.
I don't really know what the for loop should look like. I was thinking about creating some sort of alphabet list and by looping through that creating new words but I don't know how to choose what parts of the original word should remain. The new words can be appended to a list to be returned.
import string
def make_new_words(start_word):
"""create new words from given start word and returns new words"""
new_words = []
for i, letter in enumerate(start_word):
word_as_list = list(start_word)
for char in string.ascii_lowercase:
word_as_list[i] = char
new_words.append("".join(word_as_list))
return new_words
lowercase is just a string containing the lowercase letters...
We want to change each letter of the original word (here w) so we
iterate on the letters of w, but we'll mostly need the index of the letter, so we do our for loop on enumerate(w).
First of all, in python strings are immutable so we build a list x from w... lists are mutable
Now a second, inner loop on the lowercase letters: we change the current element of the x list accordingly (having changed x, we need to reset it before the next inner loop) and finally we print it.
Because we want to print a string rather than the characters in a list, we use the join method of the null string '' that glue together the elements of x using, of course, the null string.
I have not reported the output but it's exactly what you've asked for, just try...
from string import lowercase
w = 'car'
for i, _ in enumerate(w):
x = list(w)
for s in lowercase:
x[i] = s
print ''.join(x)
import string
all_letters = string.ascii_lowercase
def make_new_words(start_word):
for index, letter in enumerate(start_word):
template = start_word[:index] + '{}' + start_word[index+1:]
for new_letter in all_letters:
print template.format(new_letter)
You can do this with two loops, by looping over the word and then looping over a range for all letters. By keeping an index for the first loop, you can use a slice to construct your new strings:
for index in enumerate(start_word):
for let in range(ord('a'), ord('z')+1):
new_words.append(start_word[:index] + chr(let) + start_word[index+1:])
This could work as a brute-force approach, although you might end up with some performance issues when you go to try it with longer words.
It also sounds like you might want to constrain it only to words that exist in a dictionary at some point, which is a whole other can of worms.
But for right now, for three-letter words, you're onto something of the right track, although I worry that the question might be a little too specific for Stack Overflow.
First, you will probably have more success if you loop through the index for the word, rather than the letter:
alphabet = 'abcdefghijklmnopqrstuvwxyz'
for i in range(len(start_word)):
Then, you can use a slice to grab the letters before and after the index.
for letter in alphabet:
new_word = start_word[:i] + letter + start_word[i + 1:]
Another approach is given above, which casts the string to a list. That works around the fact that python will disallow simply setting start_word[i] = letter, which you can read about here.
My code
beginning = input("What would you like to acronymize? : ")
second = beginning.upper()
third = second.split()
fourth = "".join(third[0])
print(fourth)
I can't seem to figure out what I'm missing. The code is supposed to the the phrase the user inputs, put it all in caps, split it into words, join the first character of each word together, and print it. I feel like there should be a loop somewhere, but I'm not entirely sure if that's right or where to put it.
Say input is "Federal Bureau of Agencies"
Typing third[0] gives you the first element of the split, which is "Federal". You want the first element of each element in the sprit. Use a generator comprehension or list comprehension to apply [0] to each item in the list:
val = input("What would you like to acronymize? ")
print("".join(word[0] for word in val.upper().split()))
In Python, it would not be idiomatic to use an explicit loop here. Generator comprehensions are shorter and easier to read, and do not require the use of an explicit accumulator variable.
When you run the code third[0], Python will index the variable third and give you the first part of it.
The results of .split() are a list of strings. Thus, third[0] is a single string, the first word (all capitalized).
You need some sort of loop to get the first letter of each word, or else you could do something with regular expressions. I'd suggest the loop.
Try this:
fourth = "".join(word[0] for word in third)
There is a little for loop inside the call to .join(). Python calls this a "generator expression". The variable word will be set to each word from third, in turn, and then word[0] gets you the char you want.
works for me this way:
>>> a = "What would you like to acronymize?"
>>> a.split()
['What', 'would', 'you', 'like', 'to', 'acronymize?']
>>> ''.join([i[0] for i in a.split()]).upper()
'WWYLTA'
>>>
One intuitive approach would be:
get the sentence using input (or raw_input in python 2)
split the sentence into a list of words
get the first letter of each word
join the letters with a space string
Here is the code:
sentence = raw_input('What would you like to acronymize?: ')
words = sentence.split() #split the sentece into words
just_first_letters = [] #a list containing just the first letter of each word
#traverse the list of words, adding the first letter of
#each word into just_first_letters
for word in words:
just_first_letters.append(word[0])
result = " ".join(just_first_letters) #join the list of first letters
print result
#acronym2.py
#illustrating how to design an acronymn
import string
def main():
sent=raw_input("Enter the sentence: ")#take input sentence with spaces
for i in string.split(string.capwords(sent)):#split the string so each word
#becomes
#a string
print string.join(i[0]), #loop through the split
#string(s) and
#concatenate the first letter
#of each of the
#split string to get your
#acronym
main()
name = input("Enter uppercase with lowercase name")
print(f'the original string = ' + name)
def uppercase(name):
res = [char for char in name if char.isupper()]
print("The uppercase characters in string are : " + "".join(res))
uppercase(name)