Parsing Through HTLM Style .txt File

I'm trying to read in a txt file with a series of messages describing what is happening during a sporting event. The general format seems to be based on HTML but the file is given as .txt. I'm able to open the file and save it as a variable using fscanf (not sure if this is the most appropiate way for this application). I'm having trouble wrapping my head around how to search for blocks of code that I want to record for further analysis. For example one of things ill be doing is looking for a block like the one below.

<FLAG>

<ID>e9f40b4b-decd-4b47-ae83-e6f9c972c570</ID>

<DT>01.07.2023 16:30:00.000</DT>

<FL>Green</FL>

<LV>Track</LV>

<FI />

</FLAG>

So in plain English i want to look for every time there is <FLAG> and then record the time of day which is denoted by <DT>. I'm pretty rusty with my MATLAB never any reading from .txt files when i was at my best so I think once I get the hand of reading and searching through the file I'll be able to figure it all out from there.

Answer 1

[Ganesh]

Hi @Adam Holland,

You can consider using the "readstruct()" function in MATLAB. It allows you to input an "XML" file and parses it into a structure. Please find the code implementation of the same below:

a = readstruct('Data.txt',FileType="xml")

a = struct with fields:
    FLAG: [1x2 struct]

% You can now access the fields like any normal MATLAB structure
a.FLAG(1)

ans = struct with fields:
    ID: "e9f40b4b-decd-4b47-ae83-e6f9c972c570"
    DT: 01.07.2023 16:30:00.000
    FL: "Green"
    LV: "Track"
    FI: ""

for i=1:length(a.FLAG)
    disp(num2str(i)+ "  --  "+a.FLAG(i).ID)
end

1  --  e9f40b4b-decd-4b47-ae83-e6f9c972c570
2  --  e9f40b4b-decd-4b47-ae83-e6f9c972c571

You can read up more on readstruct from the following documentation:

https://www.mathworks.com/help/matlab/ref/readstruct.html

[Ganesh]

I have added two structures, similar to the one mentioned in the question, in the ".txt" file and enclosed both of them into a "Data" attribute.

[Adam Holland]

Thanks so much! I really like how doing it this way breaks it down into a structure variable. For some reason it says that my file isnt a valid xml format but I'll have to keep this method in mind for future projects.

[Ganesh]

Do refer to the ".txt" file attached. You might be missing to enclose the whole data within a tag.

Answer 2

[Hassaan]

% Open the file
fileID = fopen('your_file.txt', 'r');
if fileID == -1
    error('Could not open file');
end

% Read the file
fileContent = fscanf(fileID, '%c');
fclose(fileID);

% Find all occurrences of <FLAG> blocks
flagStart = strfind(fileContent, '<FLAG>');
flagEnd = strfind(fileContent, '</FLAG>');

for i = 1:numel(flagStart)
    % Extract the FLAG block
    flagBlock = fileContent(flagStart(i):flagEnd(i)+6); % +6 to include </FLAG>
    
    % Find and extract the time of day (DT)
    dtStart = strfind(flagBlock, '<DT>') + 4;
    dtEnd = strfind(flagBlock, '</DT>') - 1;
    timeOfDay = flagBlock(dtStart:dtEnd);
    
    % Display or save the time of day
    disp(['Time of day: ' timeOfDay]);
end

------------------------------------------------------------------------------------------------------------------------------------------------

If you find the solution helpful and it resolves your issue, it would be greatly appreciated if you could accept the answer. Also, leaving an upvote and a comment are also wonderful ways to provide feedback.

Professional Interests

• Technical Services and Consulting
• Embedded Systems | Firmware Developement | Simulations
• Electrical and Electronics Engineering

Feel free to contact me.

[Adam Holland]

Works perfectly. Thanks so much!

[Hassaan]

@Adam Holland You are welcome.

------------------------------------------------------------------------------------------------------------------------------------------------

If you find the solution helpful and it resolves your issue, it would be greatly appreciated if you could accept the answer. Also, leaving an upvote and a comment are also wonderful ways to provide feedback.

Professional Interests

• Technical Services and Consulting
• Embedded Systems | Firmware Developement | Simulations
• Electrical and Electronics Engineering

Feel free to contact me.