How to Find a Substring in MATLAB

By Michael Carroll

Search through text in MATLAB with
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Strings of text are stored in MATLAB as vectors (single-row matrices). Individual characters in strings can be retrieved just as elements in a vector (e.g., stringname(4)). MATLAB also includes a number of commands to help you work with strings. Use the "strfind" command to search a string for a particular character or set of characters (substring).

Type the following command in the Command Window to create a new string, being sure to use single quotation marks:

mystring = 'This is an example string.';

Use "strfind" to search "mystring" for the letter "i:"


The numbers 3, 6 and 23 are returned in a vector. These numbers correspond to the indices in "mystring" where "i" was found (the third, sixth and 23rd letters).

Use a string for the second argument to find a longer substring:


The number 12 is returned. This corresponds to the 12th character in the string, where the word "example" begins.