palindrome = regexp(chr, '(.{3,}).?(??@fliplr($1))', 'match')palindrome =1×1 cell array{'neveroddoreven'}The dynamic expression reverses the order of the letters that make up the character
vector, and then attempts to match as much of the reversed-order vector as possible. This
requires a dynamic expression because the value for $1 relies on the value of the token
(.{3,}).Dynamic expressions in MATLAB have access to the currently active workspace. This
means that you can change any of the functions or variables used in a dynamic expression
just by changing variables in the workspace. Repeat the last command of the example
above, but this time define the function to be called within the expression using a function
handle stored in the base workspace:fun = @fliplr;palindrome = regexp(chr, '(.{3,}).?(??@fun($1))', 'match')palindrome =1×1 cell array{'neveroddoreven'}Commands That Serve a Functional Purpose — (?@cmd)
The (?@cmd) operator specifies a MATLAB command that regexp or regexprep is to
run while parsing the overall match expression. Unlike the other dynamic expressions in
MATLAB, this operator does not alter the contents of the expression it is used in. Instead,
you can use this functionality to get MATLAB to report just what steps it is taking as it
parses the contents of one of your regular expressions. This functionality can be useful in
diagnosing your regular expressions.The following example parses a word for zero or more characters followed by two
identical characters followed again by zero or more characters:regexp('mississippi', '\w*(\w)\1\w*', 'match')2 Program Components