Function that give the number of words - python

I'm doing a function that give the number of words in a sentence.
Example: " Hello L World " there are 3 "words" (A letter is counted like a word).
Here is my code:
def number_of_word(s):
"""
str -> int
"""
# i : int
i = 0
# nb_word : int
nb_word = 0
if s == "":
return 0
else:
while i < len(s)-1:
if ((s[i] != " ") and (s[i+1] == " ")):
nb_word = nb_word + 1
i = i + 1
else:
i = i + 1
if s[len(s)-1] != " ":
nb_word = nb_word + 1
return nb_word
else:
return nb_word
I tried my function and I think it works. But, I also think there is a better way to do a function that do the same thing in an easier way.
Can you tell me if you know one better function? Or any comments on mine?
I hade to use:
if s == "":
return 0
else:
...........
because if I didn't, my function didn't work for number_of_word("")

If you define words as character sequences separated by one or more whitespaces, then you can simply use the split method of strings to split to words,
and then len to get their count:
def number_of_word(s):
return len(s.split())
From the documentation (emphasis mine):
split(...) method of builtins.str instance
S.split(sep=None, maxsplit=-1) -> list of strings
Return a list of the words in S, using sep as the delimiter string.
If maxsplit is given, at most maxsplit splits are done. If sep is not
specified or is None, any whitespace string is a separator and empty
strings are removed from the result.

If you want you can use RegExp
import re
def number_of_word(s):
pattern = r'\b\w+\b'
return len(re.findall(pattern, s))

If you can't use split or regex, I think this is the right solution:
def count(sentence):
wlist = []
word = ""
for c in sentence:
if c == " ":
wlist.append(word)
word = ""
else:
word += c
wlist.append(word)
return len(wlist)

You can use split() method :
def count(string1):
string1=string1.split()
return len(string1)
print(count(" Hello L World "))
output:
3

I can't use more python' functions than just "len".
So, I can't use split or RegExp.
So I want to make this function with just basic code and len.

Well, since the requirements were published, here's a way to do this without calling any library functions:
def count_words(sentence):
count, white = 0, True
for character in sentence:
if character not in " \t\n\r":
if white:
count += 1
white = False
else:
white = True
return count

Related

how to extract a sentence from string in python using simple for loop?

str1 = "srbGIE JLWokvQeR DPhyItWhYolnz"
Like I want to extract I Love Python from this string. But I am not getting how to.
I tried to loop in str1 but not successful.
i = str1 .index("I")
for letter in range(i, len(mystery11)):
if letter != " ":
letter = letter+2
else:
letter = letter+3
print(mystery11[letter], end = "")
In your for loop letter is an integer. In the the first line of the loop you need to compare mystery[11] with " ":
if mystery11[letter] != " ":
You can use a dict here, and have char->freq mapping of the sentence in it and create a hash table.
After that you can simply iterate over the string and check if the character is present in the hash or not, and if it is present then check if its count is greater than 1 or not.
Don't know if this will solve all your problems, but you're running your loop over the indices of the string, This means that your variable letter is an integer not a char. Then, letter != " " is always true. To select the current letter you need to do string[letter]. For example,
if mystery11[letter] != " ":
...
Here's how I'd go about:
Understand the pattern of the input: words are separated by blank spaces and we should get every other letter after the first uppercase one.
Convert string into a list;
Find the first uppercase letter of each element and add one so we are indexing the next one;
Get every other char from each word;
Join the list back into a string;
Print :D
Here's the code:
def first_uppercase(str):
for i in range(0, len(str)):
if word[i].istitle():
return i
return -1
def decode_every_other(str, i):
return word[i::2]
str1 = "srbGIE JLWokvQeR DPhyItWhYolnz"
# 1
sentence = str1.split()
clean_sentence = []
for word in sentence:
# 2
start = first_uppercase(word) + 1
# 3
clean_sentence.append(decode_every_other(word, start))
# 4
clean_sentence = ' '.join(clean_sentence)
print("Input: " + str1)
print("Output: " + clean_sentence)
This is what I ended up with:
Input: srbGIE JLWokvQeR DPhyItWhYolnz
Output: I Love Python
I've added some links to the steps so you can read more if you want to.
def split(word):
return [char for char in word]
a = input("Enter the original string to match:- ")
b = input("Enter the string to lookup for:- ")
c = split(a)
d = split(b)
e = []
for i in c:
if i in d:
e.append(i)
if e == c:
final_string = "".join(e)
print("Congrats!! It's there and here it is:- ", final_string)
else:
print("Sorry, the string is not present there!!")

Find words in a string of text (where letters aren't consecutive)

I'd like write code to find specific instances of words in a long string of text, where the letters making up the word are not adjacent, but consecutive.
The string I use will be thousands of characters long, but a as a shorter example... If I want to find instances of the word "chair" within the following string, where each letter is no more than 10 characters from the previous.
djecskjwidhl;asdjakimcoperkldrlkadkj
To avoid the problem of finding many instances in a large string, I'd prefer to limit the distance between every two letters to 10. So the word chair in the string abcCabcabcHabcAabdIabcR would count. But the word chair in the string abcCabcabcabcabcabcabcabcabHjdkeAlcndInadhR would not count.
Can I do this with python code? If so I'd appreciate an example that I could work with.
Maybe paste the string of text or use an input file? Have it search for the word or words I want, and then identify if those words are there?
Thanks.
This code below will do what you want:
will_find = "aaaaaaaaaaaaaaaaaaaaaaaabcCabcabcHabcAabdIabcR"
wont_find = "abcCabcabcabcabcabcabcabcabHjdkeAlcndInadhR"
looking_for = "CHAIR"
max_look = 10
def find_word(characters, word):
i = characters.find(word[0])
if i == -1:
print("I couldnt find the first character ...")
return False
for symbol in word:
print(characters[i:i + max_look+1])
if symbol in characters[i:i + max_look+1]:
i += characters[i: i + max_look+1].find(symbol)
print("{} is in the range of {} [{}]".format(symbol, characters[i:i+ max_look], i))
continue
else:
print("Couldnt find {} in {}".format(symbol, characters[i: i + max_look]))
return False
return True
find_word(will_find, looking_for)
print("--------")
find_word(wont_find, looking_for)
An alternative, this may also work for you.
long_string = 'djecskjwidhl;asdjakimcoperkldrlkadkj'
check_word = 'chair'
def substringChecker(longString, substring):
starting_index = []
n , derived_word = 0, substring[0]
for i, char in enumerate(longString[:-11]):
if char == substring[n] and substring[n + 1] in longString[i : i + 11]:
n += 1
derived_word += substring[n]
starting_index.append(i)
if len(derived_word) == len(substring):
return derived_word == substring, starting_index[0]
return False
print(substringChecker(long_string, check_word))
(True, 3)
To check if the word is there:
string = "abccabcabchabcaabdiabcr"
word = "chair"
while string or word:
index = string[:10].find(word[0])
if index > -1:
string = string[index+1:]
word = word[1:]
continue
if not word:
print("found")
else:
break

Python iterations mischaracterizes string value

For this problem, I am given strings ThatAreLikeThis where there are no spaces between words and the 1st letter of each word is capitalized. My task is to lowercase each capital letter and add spaces between words. The following is my code. What I'm doing there is using a while loop nested inside a for-loop. I've turned the string into a list and check if the capital letter is the 1st letter or not. If so, all I do is make the letter lowercase and if it isn't the first letter, I do the same thing but insert a space before it.
def amendTheSentence(s):
s_list = list(s)
for i in range(len(s_list)):
while(s_list[i].isupper()):
if (i == 0):
s_list[i].lower()
else:
s_list.insert(i-1, " ")
s_list[i].lower()
return ''.join(s_list)
However, for the test case, this is the behavior:
Input: s: "CodesignalIsAwesome"
Output: undefined
Expected Output: "codesignal is awesome"
Console Output: Empty
You can use re.sub for this:
re.sub(r'(?<!\b)([A-Z])', ' \\1', s)
Code:
import re
def amendTheSentence(s):
return re.sub(r'(?<!\b)([A-Z])', ' \\1', s).lower()
On run:
>>> amendTheSentence('GoForPhone')
go for phone
Try this:
def amendTheSentence(s):
start = 0
string = ""
for i in range(1, len(s)):
if s[i].isupper():
string += (s[start:i] + " ")
start = i
string += s[start:]
return string.lower()
print(amendTheSentence("CodesignalIsAwesome"))
print(amendTheSentence("ThatAreLikeThis"))
Output:
codesignal is awesome
that are like this
def amendTheSentence(s):
new_sentence=''
for char in s:
if char.isupper():
new_sentence=new_sentence + ' ' + char.lower()
else:
new_sentence=new_sentence + char
return new_sentence
new_sentence=amendTheSentence("CodesignalIsAwesome")
print (new_sentence)
result is codesignal is awesome

How to ignore capitalization BUT return same capitalization as input

My code intends to identify the first non-repeating string characters, empty strings, repeating strings (i.e. abba or aa), but it's also meant to treat lower and upper case input as the same character while returning the accurate non-repeating character in it's orignial case input.
def first_non_repeat(string):
order = []
counts = {}
for x in string:
if x in counts and x.islower() == True:
counts[x] += 1
else:
counts[x] = 1
order.append(x)
for x in order:
if counts[x] == 1:
return x
return ''
My logic on line 5 was that if I make all letter inputs lowercase, then it would iterate through the string input and not distinguish by case. But as of now, take the input 'sTreSS'and output is 's' when really I need 'T'. If the last two S's were lowercase, then it would be 'T' but I need code flexible enough to handle any case input.
When comparing two letters, use lower() to compare the characters in a string. An example would be:
string ="aabcC"
count = 0
while count < len(string) - 1:
if string[count].lower() == string[count + 1].lower():
print "Characters " + string[count] + " and " + string[count + 1] + " are repeating."
count += 1
Here's little change u can make to your code to make it work.
def first_non_repeat(string):
order = []
counts = {}
for x in string:
char_to_look = x.lower() #### convert to lowercase for all operations
if char_to_look in counts :
counts[char_to_look] += 1
else:
counts[char_to_look] = 1
order.append(char_to_look)
for x in string: ### search in the string instead or order, character and order will remain the same, except the case. So again do x.lower() to search in count
if counts[x.lower()] == 1:
return x
return ''1
The point is that x in counts is searched for in a case-insensitive way. You have to implement your own case insensitive Dictionary, or use regular expressions to detect repeating letters:
import re
def first_non_repeat(string):
r = re.compile(r'([a-z])(?=.*\1)', re.I|re.S)
m = r.search(string)
while m:
string = re.sub(m.group(1), '', string, re.I)
m = r.search(string)
return string[0]
print(first_non_repeat('sTreSS'))
See the Python demo
The ([a-z])(?=.*\1) regex finds any ASCII letter that also appears somewhere ahead (note that ([a-z]) captures the char into Group 1 and the (?=.*\1) is a lookahead where \1 matches the same char captured into Group 1 after any 0+ characters matched with .* pattern, and re.S flag helps support strings with linebreaks).
The re.sub will remove all the found letters in a case insensitive way, so we will only get unique characters in the string after the while block.

Python How to capitalize nth letter of a string

I tried this: Capitalize a string. Can anybody provide a simple script/snippet for guideline?
Python documentation has capitalize() function which makes first letter capital. I want something like make_nth_letter_cap(str, n).
Capitalize n-th character and lowercase the rest as capitalize() does:
def capitalize_nth(s, n):
return s[:n].lower() + s[n:].capitalize()
my_string[:n] + my_string[n].upper() + my_string[n + 1:]
Or a more efficient version that isn't a Schlemiel the Painter's algorithm:
''.join([my_string[:n], my_string[n].upper(), my_string[n + 1:]])
x = "string"
y = x[:3] + x[3].swapcase() + x[4:]
Output
strIng
Code
Keep in mind that swapcase will invert the case whether it is lower or upper.
I used this just to show an alternate way.
This is the comprehensive solution: either you input a single word, a single line sentence or a multi line sentence, the nth letter will be converted to Capital letter and you will get back the converted string as output:
You can use this code:
def nth_letter_uppercase(string,n):
listofwords = string.split()
sentence_upper = ''
for word in listofwords:
length = len(word)
if length > (n - 1):
new_word = word[:n-1] + word[n-1].upper() + word[n:]
else:
new_word = word
sentence_upper += ' ' + new_word
return sentence_upper
calling the function defined above (I want to convert 2nd letter of each word to a capital letter):
string = '''nature is beautiful
and i love python'''
nth_letter_uppercase(string,2)
output will be:
'nAture iS bEautiful aNd i lOve pYthon'
I know it's an old topic but this might be useful to someone in the future:
def myfunc(str, nth):
new_str = '' #empty string to hold new modified string
for i,l in enumerate(str): # enumerate returns both, index numbers and objects
if i % nth == 0: # if index number % nth == 0 (even number)
new_str += l.upper() # add an upper cased letter to the new_str
else: # if index number nth
new_str += l # add the other letters to new_str as they are
return new_str # returns the string new_str
A simplified answer would be:
def make_nth_letter_capital(word, n):
return word[:n].capitalize() + word[n:].capitalize()
You can use:
def capitalize_nth(text, pos):
before_nth = text[:pos]
n = text[pos].upper()
new_pos = pos+1
after_nth = text[new_pos:]
word = before_nth + n + after_nth
print(word)
capitalize_nth('McDonalds', 6)
The outcome is:
'McDonaLds'
I think this is the simplest among every answer up there...
def capitalize_n(string, n):
return string[:n] + string[n].capitalize() + string[n+1:]
This works perfect

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