MATLAB Central Newsreader - Importing several CSV files at the same time (600 or more)

Importing several CSV files at the same time (600 or more)

BO — Mon, 01 Oct 2007 15:30:55 -0400

Hey! i need to import around 400-600 csv files to the workspace at the same time so i can take the data in those file and graph it, the issue is that i have to this trough a Gui, and using uiimport takes a lot of time. Is there a way that i can import that many files, and let the user of the gui select de directory and the number of files.
type of files: CSV files, with 3 colums each colum a variable with around 8192 points.

Re: Importing several CSV files at the same time (600 or more)

G.A.M. — Mon, 01 Oct 2007 19:33:20 -0400

BO <bianca_osorio@hotmail.com> wrote in message
<5497789.1191252685630.JavaMail.jakarta@nitrogen.mathforum.org>...
> Hey! i need to import around 400-600 csv files to the
workspace at the same time so i can take the data in those
file and graph it, the issue is that i have to this trough a
Gui, and using uiimport takes a lot of time. Is there a way
that i can import that many files, and let the user of the
gui select de directory and the number of files.
> type of files: CSV files, with 3 colums each colum a
variable with around 8192 points.

This code doesn't include a feature for limiting the number
of files in a directory, but you could add that easily:

%let user select directory from UI,
%and pass this directory as a parameter
function ProcessFiles(directory)
allFiles = dir(directory);
for k = 1 : length(allFiles)
if(strfind(allFiles(k).name, '.csv'))
processFile([directory '\' allFiles(k).name]);
end
end
end

Re: Importing several CSV files at the same time (600 or more)

BO — Tue, 02 Oct 2007 12:53:01 -0400

Hey Thank u for ur answer.. i try the code u said.. just with the directory i want... to see what it does..
%let user select directory from UI,
%and pass this directory as a parameter
function ProcessFiles ('C:\Users\Biankita\Documents\EQUIMAVENCA\DATA\RD04-1\FFTs\*.csv');
allFiles = dir('C:\Users\Biankita\Documents\EQUIMAVENCA\DATA\RD04-1\FFTs\*.csv');
for k = 1 : 100(allFiles)
if(strfind(allFiles(k).name, '.csv'))
processFile([C:\Users\Biankita\Documents\EQUIMAVENCA\DATA\RD04-1\FFTs '\' allFiles(k).name]);
end
end
end
but i get this...
??? Error: File: ProcessFiles.m Line: 3 Column: 24
Missing MATLAB operator

Re: Importing several CSV files at the same time (600 or more)

"G.A.M. — Tue, 02 Oct 2007 14:21:53 -0400

On Oct 2, 8:53 am, BO <bianca_oso...@hotmail.com> wrote:
> Hey Thank u for ur answer.. i try the code u said.. just with the directory i want... to see what it does..
> %let user select directory from UI,
> %and pass this directory as a parameter
> function ProcessFiles ('C:\Users\Biankita\Documents\EQUIMAVENCA\DATA\RD04-1\FFTs\*.csv');
> allFiles = dir('C:\Users\Biankita\Documents\EQUIMAVENCA\DATA\RD04-1\FFTs\*.csv');
> for k = 1 : 100(allFiles)
> if(strfind(allFiles(k).name, '.csv'))
> processFile([C:\Users\Biankita\Documents\EQUIMAVENCA\DATA\RD04-1\FFTs '\' allFiles(k).name]);
> end
> end
> end
> but i get this...
> ??? Error: File: ProcessFiles.m Line: 3 Column: 24
> Missing MATLAB operator

I see several potential issues:
1. Did you write the function "processFile"?
2. The parameter to your main function (ProcessFiles) should probably
be: 'C:\Users\Biankita\Documents\EQUIMAVENCA\DATA\RD04-1\FFTs'
3. You are missing the single quotes on your first parameter to
processFile.
4. your for-loop syntax looks incorrect.

Re: Importing several CSV files at the same time (600 or more)

Dan Hensley — Tue, 02 Oct 2007 14:24:13 -0400

BO wrote:
> Hey! i need to import around 400-600 csv files to the workspace at the same time so i can take the data in those file and graph it, the issue is that i have to this trough a Gui, and using uiimport takes a lot of time. Is there a way that i can import that many files, and let the user of the gui select de directory and the number of files.
> type of files: CSV files, with 3 colums each colum a variable with around 8192 points.

This is a FAQ:

http://www.mit.edu/~pwb/cssm/matlab-faq.html#loopoverfiles

Dan

Re: Importing several CSV files at the same time (600 or more)

Peter Boettcher — Tue, 02 Oct 2007 16:33:22 -0400

BO <bianca_osorio@hotmail.com> writes:

> Hey Thank u for ur answer.. i try the code u said.. just with the
> directory i want... to see what it does..

> %let user select directory from UI,
> %and pass this directory as a parameter
> function ProcessFiles ('C:\Users\Biankita\Documents\EQUIMAVENCA\DATA\RD04-1\FFTs\*.csv');
> allFiles = dir('C:\Users\Biankita\Documents\EQUIMAVENCA\DATA\RD04-1\FFTs\*.csv');
> for k = 1 : 100(allFiles)
> if(strfind(allFiles(k).name, '.csv'))
> processFile([C:\Users\Biankita\Documents\EQUIMAVENCA\DATA\RD04-1\FFTs '\' allFiles(k).name]);
> end
> end
> end
> but i get this...
> ??? Error: File: ProcessFiles.m Line: 3 Column: 24
> Missing MATLAB operator

You were not supposed to replace "directory" with your directory. It
was supposed to be a function which you called using your directory as
a parameter.

If you don't know what I am talking about, take a break from this task
and read the "Getting Started" part of the MATLAB documentation.

-Peter