Prev: call a UNIX function from an .m file
Next: SSMCMA
From: Paul on 19 Jul 2010 17:37
Hello,
I have been having an issue working with multiple data files in a loop.
I have several data files...
input001
input002
input003 ...

which I have loaded by

files=dir('input*')
for i=1:length(files)
eval(['load ' files(i).name]);

At this point (inside the loop), I want to make a vector out of column #1 in files(1), but when I attempt this line...

x=files(1).name(:,1)

it assings the string 'i' to x, instead of a data column.

Can anyone help? Am I missing a simple tag?

Thanks so much!
From: Steven_Lord on 19 Jul 2010 17:43


"Paul " <palex71(a)hotmail.com> wrote in message
news:i22gi0$cdq$1(a)fred.mathworks.com...
> Hello,
> I have been having an issue working with multiple data files in a loop.
> I have several data files...
> input001
> input002
> input003 ...
>
> which I have loaded by
>
> files=dir('input*')
> for i=1:length(files)
> eval(['load ' files(i).name]);

NO. DO NOT DO THIS.

Instead, call LOAD with an output argument:

data = load(files(i).name);

Then you can index into data however you want.

> At this point (inside the loop), I want to make a vector out of column #1
> in files(1), but when I attempt this line...
>
> x=files(1).name(:,1)
>
> it assings the string 'i' to x, instead of a data column.

That is the correct behavior. files(1).name is 'input001' and the first
column of that char array is the character 'i'.

--
Steve Lord
slord(a)mathworks.com
comp.soft-sys.matlab (CSSM) FAQ: http://matlabwiki.mathworks.com/MATLAB_FAQ
To contact Technical Support use the Contact Us link on
http://www.mathworks.com

From: per isakson on 19 Jul 2010 17:52
"Paul " <palex71(a)hotmail.com> wrote in message <i22gi0$cdq$1(a)fred.mathworks.com>...
> Hello,
> I have been having an issue working with multiple data files in a loop.
> I have several data files...
> input001
> input002
> input003 ...
>
> which I have loaded by
>
> files=dir('input*')
> for i=1:length(files)
> eval(['load ' files(i).name]);
>
> At this point (inside the loop), I want to make a vector out of column #1 in files(1), but when I attempt this line...
>
> x=files(1).name(:,1)
>
> it assings the string 'i' to x, instead of a data column.
>
> Can anyone help? Am I missing a simple tag?
>
> Thanks so much!

files(1).name is the name of the file and files(1).name(:,1) is the first character of the name of the file, i.e. "i".

Read the documentation of load, which recommend against using this syntax when the filename is the value of a variable.

What's in the files?

/ per
From: Paul on 20 Jul 2010 13:51
Thanks, guys... it is working. :)
 | 
Pages: 1
Prev: call a UNIX function from an .m file
Next: SSMCMA