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Matlab data extracting

  1. Jan 21, 2006 #1
    Ok I have a .dat file containing these datas:

    Date and Time : 120106 12:31:32 12:31:39
    Location: 1509123
    Bearing: 135
    Angle : 30

    Scan No. Coordinates PhotonCount
    255 12 1
    255 45 32
    255 34 1231
    255 21 54321
    255 24 1231


    So, you can see that the file contains an array containing three coloums.

    I want to extract these three coloums into an array using MATLAB

    Can someone write an .m file that will do the job ?

    Thank You
  2. jcsd
  3. Jan 21, 2006 #2


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    Science Advisor

    Just edit the text file so that it contains only the 3 columns of data and nothing else and then give this file some name, say tmp.dat. Then just load it into matlab using "load tmp.dat".

    This will create a matrix called "tmp" in matlab that contains all three columns of data. Then extract each column to a vector using "x=tmp(:,1)", "y=tmp(:,2)" etc.
  4. Jan 22, 2006 #3
    I have more than 2000 of such files. It cannot be done manually.
    I need matlab to automatically to do it.
  5. Jan 23, 2006 #4

    jim mcnamara

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    Staff: Mentor

    FWIW - if you are working in any flavor of UNIX the text editing capabilities can do what you want in:
    Code (Text):

    for file in `ls /path/to/files/*.dat`
           sfile=`basename $file`
           grep -v -e Date -e Scan -e Loca -e Bear $file > /new/path/$file
    All that's left = columns of numbers... in 2000 new files. The old ones are not changed.
  6. Jan 23, 2006 #5


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    Science Advisor

    Just use fscanf; intitally call it once for each of the first 6 lines, then use it once more to read the 3 columns into a matrix.
  7. Jan 23, 2006 #6
    create save and load functions...so that the save will emulate the structure of the files that you have...then create teh load function based off the save function and you should eb able to extract all information adn then leave out the ones you want.
  8. Feb 1, 2006 #7
    thanks everybody
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