Question about using 'load' to load an .m file

I'm currently trying to use the load command to pull data from an existing .m file I've downloaded from the internet, but the .m file is coming in as a [0x0] vector, and it shouldn't be.

I'm getting the message

"Attempted to access sampleDataFlow(:,1); index out of bounds because size(sampleDataFlow)=[0,0]."

when I attempt to define a variable to column 1. Any idea why this would be happening?

Thanks

Answer 1

[Ryan G]

Although you can use the load command with an m-file, in my humble opinion, this would not be the ideal way to transfer data nor read data.

My suggestion would be to utilize the Import Tool available in the Home tab (R2012b). It's available in other versions but I like to be forward thinking.

This will allow you to utilize a GUI for the first time you import making it easy to determine if the data was imported correctly and easy to change the import method to achieve desired results. Once you're established the correct method you will be able to automatically generate a script or function to do it again and again.

The link above describes it better than I ever could.

[Robert]

I appreciate your answer, however for the purpose of my work I have to understand how to use the load command with the m-file, as it is what I will primarily be using in a current class.

[Ryan G]

Yikes! Tell your instructor this doesn't make sense!

Are you sure it is an m-file? As in, it has a .m extension and you double click it you can read the contents and edit them like a txt file?

[Robert]

Yes, it is definitely an m-file online, but when I save it and open it in matlab using 'load', it comes in as [0x0]. I don't understand why.

[Ryan G]

What are the first couple lines inside the file?

Say I create a MATLAB file, and put the contents as

 1 2 3 
 4 5 6

save it as myfile.m, then use the command

x = load('myfile.m')

You will see it loads the data into x and displays this in the command window. Try this out first and make sure it works. It should load it like an ascii file I believe. What does the m-file look like when you open it? What type of data is inside?

[Robert]

First couple of lines look like this. The 3 columns continue for a while though. It's basically just a large collection of data.

0.00  0.00  0.00
2.00  0.54  0.54
4.00  2.54  1.48
6.00  4.51  0.49
8.00  5.47  0.46

When I open the m-file, it is displayed as blank when I double click on it.

[Ryan G]

The two things you say are kind of opposing each other. On the one hand you say it contains the data on the other you say when you open it it's empty. How do you know what data it contains if it's empty when you open it?

[Robert]

I mean to say, the file online contains the data. When I import it however, the data disappears. I'm sorry I didn't make that clear.

[Ryan G]

I would verify that hte data exists in the downloaded file. It sounds like the issue is coming up between downloading the file and the file that exists locally

[Robert]

That's also what I think. I'm not sure what the issue would be. I'm using "save target as..." to do the download, and it hasn't ever failed me before, so I'm not sure what's going wrong. Frustrating.

Answer 2

[Walter Roberson]

Try using the -ascii option when you load()

Answer 3

[Azzi Abdelmalek]

you can get your data like you import any text file

   fid = fopen('file.m');
   line1 = fgetl(fid)
   res=line1;
   while ischar(line1)
   line1 = fgetl(fid);
   res =char(res,line1)
   end
   fclose(fid);