matlabformattingneural-networknntool

How to format data for use in nntool (MATLAB)?


In nntool, the sample data is formatted as: [0 1 -1; 2 3 1]

I have ~8000 data points in a text file. How do I format those points for use here? What does the semicolon signify?


Solution

  • From this example, that would mean each column of the input data would be separated by a ;. The Target data would be a vector like [1 2 3 4] corresponding to each row of the input data.

    E.g. if you want to learn the XOR truth table:

    X Y XOR
    0 0 0
    0 1 1
    1 0 1
    1 1 0
    

    Then the Input matrix is

    X Y 
    0 0 
    0 1 
    1 0 
    1 1 
    

    And the Target is

    XOR
    0
    1
    1
    0
    

    And therefore, your data should be formatted as [0 0 1 1;0 1 0 1] for the input (each column is separated by a ;) and the target data would be [0 1 1 0].

    As far as your 8000 point data file is concerned, you can load it into a variable in your workspace and let nntool read the input matrix from your workspace or a .mat file (after you've saved the variable into it).