count

Count the number of occurrences of the string, red, in string arrays.

You can create a string using double quotes.

str = "paired with red shoes"

str = 
"paired with red shoes"

To count the occurrences of red, use the count function. In this example, the result is 2 because red is also part of the word paired.

A = count(str,"red")

A = 
2

Create a 2-by-1 string array.

str = ["red green red red blue blue green";
       "green red blue green green blue"]

str = 2x1 string
    "red green red red blue blue green"
    "green red blue green green blue"

Count the occurrences of red in each element of str. If str is a string array or cell array of character vectors, then A is a numeric array that has the same size.

A = count(str,"red")

A = 2×1

     3
     1

Since R2020b

Create a string array that contains addresses.

str = ["221B Baker St.","Tour Eiffel Champ de Mars","4059 Mt Lee Dr."]

str = 1x3 string
    "221B Baker St."    "Tour Eiffel Champ de Mars"    "4059 Mt Lee Dr."

To count the digits in each address, first create a pattern that matches a single digit. The number of times this pattern occurs in a string equals the number of digits in the string.

Create the pattern by calling the digitsPattern function with 1 as the input argument. When you do this, it matches a single digit (such as 2) instead of an arbitrary sequence of digits (such as 221 or 4059).

pat = digitsPattern(1)

pat = pattern
  Matching:

    digitsPattern(1)

Then call the count function with str and pat as inputs.

A = count(str,pat)

A = 1×3

     3     0     4

Similarly, you can count the number of letters (not including digits, spaces, or punctuations marks) by using the pattern created by lettersPattern(1).

A = count(str,lettersPattern(1))

A = 1×3

     8    21     7

Count sequences consisting of one or more digits and then one letter. You can build more complex patterns by combining simple patterns. In this case, digitsPattern + lettersPattern(1) matches 221B.

pat = digitsPattern + lettersPattern(1);
A = count(str,pat)

A = 1×3

     1     0     0

For a list of functions that create pattern objects, see pattern.

Count the total number of occurrences of red and blue in a string array.

You can create strings using double quotes.

str = ["red green blue";
       "green red blue green blue"]

str = 2x1 string
    "red green blue"
    "green red blue green blue"

count returns 2 for the first string because red and blue each occur once. count returns 3 for the second string because red occurs once and blue occurs twice.

A = count(str,["red","blue"])

A = 2×1

     2
     3

Count the number of occurrences of the letter E in a string array that contains names, ignoring case.

You can create strings using double quotes.

str = ["Edgar Allan Poe";"Louisa May Alcott"]

str = 2x1 string
    "Edgar Allan Poe"
    "Louisa May Alcott"

A = count(str,'E','IgnoreCase',true)

A = 2×1

     2
     0

Count the number of times al occurs in the word alphabetical.

chr = 'alphabetical'

chr = 
'alphabetical'

A = count(chr,'al')

A = 
2