I'm attempting to solve a difference equation(adsbygoogle = window.adsbygoogle || []).push({});

y(k+1) = -0.5*y(k) + x(k)

where y(0) = 0 and x(k) is in my case a unit step function ie = 1

well, i'm trying to solve this using a for loop, but am having some trouble. The code i've generated gets an error, "Index into matrix is negative or zero."

Any ideas?

My code is below.

k = 0 ; %counter variable

y = 0; %y(k)

x = 1; %x(k), unit step function

for k = 0 : 5

y(k+1) = -.5*y(k) + x;

y(k) = y(k+1)

end

Thanks for any help.

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# Matlab for loop and difference equation question

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