Count the number of occurrences of the string, red, in string arrays.
Starting in R2017a, you can create a string using double quotes.
str = "paired with red shoes"
str =
"paired with red shoes"
If you are using R2016b, then use the string function instead of double quotes.
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.
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.
Starting in R2017a, 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.
You can also select a web site from the following list:
How to Get Best Site Performance
Select the China site (in Chinese or English) for best site performance. Other MathWorks country sites are not optimized for visits from your location.