Michael Ewens » matlab

Create a dated log file in Matlab

Michael Ewens — Thu, 23 Jul 2009 16:33:32 +0000

If you change your datasets or code a lot in Matlab, it is smart to keep track of the results over time (trust me….). The ‘diary’ function allows you to record all output of your scripts to a file. Append your main .m file with the following code to create a diary/log file that is uniquely dated to the time (to the minute) that you ran the script:

date_now = clock;
date_now = strcat(num2str(date_now(1)),'_',num2str(date_now(2)),'_', num2str(date_now(3)), num2str(date_now(4)), num2str(date_now(5)));
diary(strcat('log', date_now,'.log'));

Simple Bootstrap Sample in Matlab

Michael Ewens — Wed, 25 Mar 2009 08:39:38 +0000

Let x be your vector of data which has to be bootstrapped. For each instance of the loop write:

x = x(floor(rows(x)*rand(rows(x),1))+1,:); % bootstrap observations

Now we have a matrix with the same number of rows and columns, but with re-sampled data with replacement. A one line bootstrap! (Modified code from John Cochrane)

Using Remote Files in Matlab

Michael Ewens — Tue, 24 Mar 2009 08:37:31 +0000

If you have an FTP server set-up somewhere with ample space and bandwidth, Matlab can store and retrieve its files and data remotely. Just use these simple commands to connect and disconnect:

% File to connect to the server where my Matlab/data resides


% connect to the db

f = ftp('yourdomain.com', 'user', 'password');
% change the directory

cd(f, 'matlab');
% now change the directory that we want to download the directory

cd '/';
% Download the directory

mget(f, 'remote_dir');
% *****************

% INSERT PROGRAM HERE

% *****************
% when done move a directory here

cd ..

% now move the directory back to the server

mput(f, 'remote_dir');

disp('Files have been put back on the server');

% close the connect close(f);