Count frequency of words in a list and sort by frequency

Question

I am using Python 3 3  I need to create two lists  one for the unique words and the other for the frequencies of the word   I have to sort the unique word list based on the frequencies list so that the word with the highest frequency is first in the list    I have the design in text but am uncertain how to implement it in Python    The methods I have found so far use either Counter or dictionaries which we have not learned  I have already created the list from the file containing all the words but do not know how to find the frequency of each word in the list  I know I will need a loop to do this but cannot figure it out   Here s the basic design             original list     the    car         newlst       frequency       for word in the original list        if word not in newlst             newlst append word             set frequency   1        else            increase the frequency  sort newlst based on frequency list

User · Answer

The ideal way is to use a dictionary that maps a word to it s count  But if you can t use that  you might want to use 2 lists - 1 storing the words  and the other one storing counts of words  Note that order of words and counts matters here  Implementing this would be hard and not very efficient

User · Answer

use this  from collections import Counter list1   apple   egg   apple   banana   egg   apple   counts   Counter list1  print counts    Counter   apple   3   egg   2   banana   1

User · Answer

You can use   from collections import Counter   It supports Python 2 7 read more information here  1    gt  gt  gt c   Counter  abracadabra    gt  gt  gt c most common 3     a   5     r   2     b   2     use dict   gt  gt  gt d  1  one   2  one   3  two    gt  gt  gt c   Counter d values       one   2     two   1     But  You have to read the file first  and converted to dict   2  it s the python docs example use re and Counter    Find the ten most common words in Hamlet  gt  gt  gt  import re  gt  gt  gt  words   re findall r  w    open  hamlet txt   read   lower     gt  gt  gt  Counter words  most common 10     the   1143     and   966     to   762     of   669     i   631      you   554      a   546     my   514     hamlet   471     in   451

User · Answer

Using Counter would be the best way  but if you don t want to do that  you can implement it yourself this way     The list you already have word list     words         other    words     Get a set of unique words from the list word set   set word list    create your frequency dictionary freq        iterate through them  once per unique word  for word in word set      freq word    word list count word    float len word list     freq will end up with the frequency of each word in the list you already have   You need float in there to convert one of the integers to a float  so the resulting value will be a float   Edit   If you can t use a dict or set  here is another less efficient way     The list you already have word list     words         other    words   unique words      for word in word list      if word not in unique words          unique words     word  word frequencies      for word in unique words      word frequencies     float word list count word     len word list   for i in range len unique words        print unique words i           word frequencies i     The indicies of unique words and word frequencies will match

User · Answer

Pandas answer   import pandas as pd original list     the    car    is    red    red    red    yes    it    is    is    is   pd Series original list  value counts     If you wanted it in ascending order instead  it is as simple as   pd Series original list  value counts   sort values ascending True

User · Answer

One way would be to make a list of lists  with each sub-list in the new list containing a word and a count   list1          this is your original list of words list2          this is a new list  for word in list1      if word in list2          list2 index word  1     1     else          list2 append  word 0     Or  more efficiently   for word in list1      try          list2 index word  1     1     except          list2 append  word 0     This would be less efficient than using a dictionary  but it uses more basic concepts

User · Answer

You can use reduce   - A functional way   words    apple banana apple strawberry banana lemon  reduce  lambda d  c  d update   c  d get c 0  1    or d  words split          returns     strawberry   1   lemon   1   apple   2   banana   2

User · Answer

Yet another solution with another algorithm without using collections   def countWords A      dic       for x in A         if not x in  dic          Python 2 7  if not dic has key x             dic x    A count x     return dic  dic   countWords   apple   egg   apple   banana   egg   apple    sorted items sorted dic items        if you want it sorted

User · Answer

words   file  test txt    r   read   split    read the words into a list  uniqWords   sorted set words    remove duplicate words and sort for word in uniqWords      print words count word   word

User · Answer

Here is code support your question is char   check for validate string count those strings alone  Hashmap is dictionary in python   def is word word      cnt  0    for c in word         if  a   lt   c  lt   z  or  A   lt   c  lt    Z  or  0   lt   c  lt    9  or c                   cnt   1    if cnt  len word         return True   return False  def words freq s     d      for i in s split        if is word i           if i in d              d i    1         else              d i    1    return d   print words freq  the the sky  is blue not green

User · Answer

Try this   words      freqs       for line in sorted original list    takes all the lines in a text and sorts them     line   line rstrip    strips them of their spaces     if line not in words   checks to see if line is in words         words append line   if not it adds it to the end words         freqs append 1   and adds 1 to the end of freqs     else          index   words index line   if it is it will find where in words         freqs index     1  and use the to change add 1 to the matching index in freqs

User · Answer

the best thing to do is    def wordListToFreqDict wordlist       wordfreq    wordlist count p  for p in wordlist      return dict zip wordlist  wordfreq     then try to               wordListToFreqDict originallist

[python] Count frequency of words in a list and sort by frequency

Examples related to python

Examples related to python-3.x

Examples related to list

Examples related to frequency

Examples related to word