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Help with MATLAB problem

  1. Feb 4, 2014 #1

    I've figured out the first part, (a), it's the second part (b) that's confusing- I've tried re-arranging the plot() function and also tinkering with y1 and y2 rather than y(t), as I get the error:

    "Subscript indices must either be real positive integers or logicals."

    Any help or advice?
  2. jcsd
  3. Feb 5, 2014 #2
  4. Feb 5, 2014 #3


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    Gold Member

    y(t) is functional notation in mathematics. In MATLAB, y(t) means the t-th element in y. In this case t is even a vector of (noninteger) values, so you end up telling MATLAB you want to look at y(0.05), which doesn't make sense since y doesnt have a 0.05th element, only a 1st, 2nd, etc... So just define y = instead of y(t) = .

    I'll get you started..
    y = exp(-t./2).*exp(-2*t);
    x = ...
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