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[MATLAB] - Getting Error

  1. Mar 24, 2010 #1
    [MATLAB] -- Getting Error

    Code:

    % Define variables for wn and z
    wn = 5;
    z1 = 0; z2 = 0.2; z3 = 0.9; z4 = 1; z5 = 2; z6 = 30;

    % Define transfer functions
    num = [wn^2];
    den1 = [1, 2*z1*wn, wn^2];
    den2 = [1, 2*z2*wn, wn^2];
    den3 = [1, 2*z3*wn, wn^2];
    den4 = [1, 2*z4*wn, wn^2];
    den5 = [1, 2*z5*wn, wn^2];
    den6 = [1, 2*z6*wn, wn^2];
    tf_1 = tf(num, den1);
    tf_2 = tf(num, den2);
    tf_3 = tf(num, den3);
    tf_4 = tf(num, den4);
    tf_5 = tf(num, den5);
    tf_6 = tf(num, den6);

    % Create plots for step response

    step(tf_1)
    step(tf_2)
    step(tf_3)
    step(tf_4)
    step(tf_5)
    step(tf_6)



    I am getting the error:

    ??? Undefined function or method 'tf' for input arguments of type 'double'.

    Error in ==> HW9_2 at 13
    tf_1 = tf(num, den1);


    Any ideas why?
     
  2. jcsd
  3. Mar 24, 2010 #2

    Choppy

    User Avatar
    Science Advisor
    Education Advisor

    Re: [MATLAB] -- Getting Error

    Have you created a function for tf?
     
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