Скачать или смотреть Find the Substring in a String with Matlab

Discover how to identify substrings in a string using Matlab effectively. Learn to find which specific characters exist in your string with practical examples.
---
This video is based on the question https://stackoverflow.com/q/63233831/ asked by the user 'Glu' ( https://stackoverflow.com/u/5380377/ ) and on the answer https://stackoverflow.com/a/63234096/ provided by the user 'Luis Mendo' ( https://stackoverflow.com/u/2586922/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: Find which substring is contained in string with Matlab

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Finding Substrings in Strings with MATLAB: A Complete Guide

Have you ever faced the challenge of determining whether specific substrings are present within a larger string in Matlab? If you're working with character variables and need to extract substrings efficiently, you might find yourself puzzled about the right approach. In this guide, we will walk through a common scenario and provide you with effective solutions to tackle the problem using Matlab.

The Problem: Identifying Substrings

Imagine you have a character variable called condition that stores a string such as:

[[See Video to Reveal this Text or Code Snippet]]

Your task is to determine if any of the following substrings are present within condition: 25, 35, or 45. The challenge arises because standard functions like contains() only tell you whether a substring is present—without specifying which one it is.

Solution: Using Regular Expressions and Cell Arrays

Approach 1: Using regexp and cellfun

One effective way to find specific substrings in Matlab is by using a combination of the regexp function along with cellfun. Here’s how you can do it:

[[See Video to Reveal this Text or Code Snippet]]

Explanation:

regexp(condition, strToFind, 'once') checks for the occurrences of each item in strToFind within the condition string.

cellfun(@ isempty, ...) efficiently checks for empty results from regexp, returning false for found instances.

The negation operator ~ converts these results into a logical array.

This logical array will have the same size as strToFind and will indicate which substrings are present in condition.

Approach 2: Using contains with cellfun

As an alternative, you can directly use the contains function in a more straightforward manner. Here’s how:

[[See Video to Reveal this Text or Code Snippet]]

Explanation:

cellfun applies the contains function to each element in strToFind.

This will return a logical array indicating the presence of each substring within condition.

Conclusion

Using the approaches outlined above, you’ll be able to easily identify which substrings are present in your string using Matlab. Whether you prefer the regex method or the simpler contains function, both methods provide effective solutions tailored to your needs.

So the next time you face the challenge of searching substrings in strings, you can apply these techniques to streamline your process and enhance your Matlab coding experience.

If you have any further questions or need clarification, feel free to leave a comment below. Happy coding!