Count occurrences of a word in string

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Counting number of occurrences (or frequency) of a word in string

Excel

  1. Using the function SUBSTITUTE & LEN functions. demo. Or
  2. Using the function COUNTIF

MySQL way

SET @paragraph := 'an apple a day keeps the doctor away';
SET @term := 'apple';

SELECT FLOOR((LENGTH(@paragraph) - LENGTH(REPLACE(@paragraph, @term, ''))) / LENGTH(@term)) AS occurrences;

/* same with the following query */
SELECT FLOOR((CHAR_LENGTH(@paragraph) - CHAR_LENGTH(REPLACE(@paragraph, @term, ''))) / CHAR_LENGTH(@term)) AS occurrences;

online example

-- Count occurrences of a string: .
SET @input = "www.google.com";
SET @separator = ".";
SELECT (LENGTH(@input ) - LENGTH(REPLACE(@input , @separator, ""))) / LENGTH(@separator) AS count_of_separator;
-- expected result: 2

-- Count occurrences of a string: og
SET @input = "www.google.com";
SET @separator = "og";
SELECT (LENGTH(@input ) - LENGTH(REPLACE(@input , @separator, ""))) / LENGTH(@separator) AS count_of_separator;
-- expected result: 1


PHP

Using the mb_substr_count (binary safe) or substr_count functions. See details on demo.

<?php

$input = 'an apple a day keeps the doctor away';
$term = 'apple';

echo substr_count($input, $term) . PHP_EOL;

$input = '一天一蘋果,醫生遠離我';
$term = '蘋果';

echo mb_substr_count($input, $term, 'UTF-8') . PHP_EOL;

BASH

data preparation

  • (1) separate each string by return_symbol [1]
  • (2) check the uniq command is exists on Cygwin of Win Os windows.png or Linux Os linux.png
  • (3) execute the following command sort <file.txt> | uniq -ic | sort -nr[2][3]

file: test.txt

#apple
#追劇
#電影
#綜藝
#Apple
#藍芽

Result of the execution of command: sort test.txt | uniq -ic | sort -nr Icon exclaim.gif insensitive

   2 #Apple
   1 #電影
   1 #追劇
   1 #藍芽
   1 #綜藝

Result of the execution of command: sort test.txt | uniq -c Icon exclaim.gif sensitive

   1 #Apple
   1 #apple
   1 #綜藝
   1 #藍芽
   1 #追劇
   1 #電影

verification of count occurrence

cat test.txt | grep -i "#apple$" | wc -l

# or
cat test.txt | grep -iw "#apple" | wc -l

Options[4]

  • -i means Ignore uppercase vs. lowercase.
  • -w means --word-regexp

References

  • replacing comma's with newlines using sed
  • text processing - Counting the occurrences of the string - Unix & Linux Stack Exchange
  • Sort and count number of occurrence of lines - Unix & Linux Stack Exchange
  • Grep - Wikibooks, open books for an open world