Obtaining data from a text file

I'm relatively new to MatLab, and I'm having trouble extracting a specific number from a text file. The text file reads as follows:

"Whatever=43

this is not it =3

start=2300"

What function do I use to return 2300 (and as a number format of some sort, like a double or a single, rather than a string)?

[Christian F]

The quotations are not actually part of the text document, btw.

Answer 1

[Adam Danz]

I've attached the sample text file to run this demo. In the 3rd line of code, a regular expression is used to search for the row of text that contains the key word "start". If you have more than 1 row of text that contains that word, you'll need to adapt this.

% read file --> char array
content  = fileread('textfile.txt'); 
% Break up each line of char array into cell of strings
contentStr = strsplit(content, '\n'); 
% Locate string that contains the key ("start")
target = contentStr{~cellfun(@isempty,regexp(contentStr, 'start'))};
% Isolate the numeric value 
val = str2double(target(regexp(target, '=')+1 : end));

% val =
%        2300

[Christian F]

I'm getting the error message:

"Undefined function or variable 'content'.

Error in noname (line 12)

contentStr = strsplit(content, '\n');"

Am I supposed to put in something for content?

[Adam Danz]

I updated my code above. The original final line was

val = str2double(regexp(target, '\d+', 'match')); 

but this wouldn't work if there were decimal values such as start = 2300.5;

[Adam Danz]

In the first line of my code I create the variable 'content'. That variable is an input in the 2nd line. It looks like you're running the 2nd line without running the first line.

[Christian F]

Oh. Oops. Yeah, the code works now! Thanks for your help and your patience!

[Adam Danz]

Great!