I'm getting an error and don't know how to fix it.

So I'm averaging a bunch of data and instead of opening up all the files manually and such, I'm using a for loop. Here's what my code looks like.

close all;
clc;
for k=1:10
    filename=sprintf('20.5in_%d.bin',k);
    fid=fopen('filename','r');
    data=fread(fid,[1,Inf],'single');
    sum=sum+data;
end
Average=sum/10;
plot(data/max(data));
plot(Average/max(Average));
close all

However, I get this error when I try to run it.

Error using fread
Invalid file identifier. Use fopen to generate a valid file identifier.

Error in in205 (line 6)
    data=fread(fid,[1,Inf],'single');
 

I'm not sure what the problem is or how to fix it. If I don't use a loop it works so any help would be greatly appreciated!!!

close all;
clc;
fid=fopen('20.5in_1.bin','r');
data=fread(fid,[1,Inf],'single');
plot(data/max(data));
close all

^the code that works without the loop

Answer 1

[David Fletcher]

The filename is the name held in the variable, the file isn't called 'filename'

fid=fopen(filename,'r')

[Rebekah Higgins]

Thanks!!! That's such a simple mistake! I can't believe I didn't catch that!

[David Fletcher]

Easily done. I swear sometimes the brain sees what it thinks it should be seeing, and not what is actually there