Combining variable from several m files to one

Hi,

I have data in 1x1 matrices. There are 178 '.mat' files each file contains 36 variables with same names but different values. I want to create a loop so that I could combine them to one file with 36 variables but 178 values, each value in one column.

Is it possible? If yes how?

Kind Regards, Mustahsan

Answer 1

[per isakson]

"Is it possible?" &nbsp yes

"If yes how?" &nbsp See example below

Comments:

• "1x1 matrices" &nbsp that's a scalar
• "36 variables" &nbsp requires a lot of typing. To save keystrokes I create name with sprintf and use '-regexp', '^p\d{2}'
• "to one file with 36 variables" &nbsp do you mean mat-file?
• "each value in one column" &nbsp do you mean that the values of the variables are column vectors?

Example:

    nF = 3;     % number of files
    nV = 4;     % number of variables

Create some mat-files

    for ii = 1 : nF
        for jj = 1 : nV
            assign( sprintf( 'p%02d', jj ), ii+jj/100 )
        end
        save( sprintf( 'mydata%02d', ii ), '-regexp', '^p\d{2}' );
        clear( '-regexp', '^p\d{2}' )
    end

Read mat-files and concatenate data

    p01 = nan( nF, 1 );
    p02 = nan( nF, 1 );
    p03 = nan( nF, 1 );
    p04 = nan( nF, 1 );

    for ii = 1 : nF
        sas = load( sprintf( 'mydata%02d', ii ), '-regexp', '^p\d{2}' );
        p01(ii,1) = sas.p01;
        p02(ii,1) = sas.p02;
        p03(ii,1) = sas.p03;
        p04(ii,1) = sas.p04;
    end

Save to one file

    save( 'mydata', '-regexp', '^p\d{2}' );
    clear( '-regexp', '^p\d{2}' )

where

    function    assign( Name, Value  )
        assignin( 'caller', Name, Value );
    end

I don't recommend the use of the function assign

[Mustahsan Majeed]

"1x1 matrices" that's a scalar yes it was a vector and I took average mean value of all and made it a scalar

"36 variables" requires a lot of typing. To save keystrokes I create name with sprintf and use '-regexp', '^p\d{2}' I am unable to use the srint command

"to one file with 36 variables" do you mean mat-file? yes I want to make one .mat file with 36 variables and in each variable I want 1 column with each cell representing one value from each of the 178 files (so every variable will be (1x178) matrice

"each value in one column" do you mean that the values of the variables are column vectors? (1x178) is the end format for each varibale

• thank you very much for your kind help *

[Mustahsan Majeed]

BTW I have a list of the variables exactly typed in, so I can use them too. But its better to learn how to do it without typing all of them.