Convolution Command: Inputs Invalid

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I am having trouble getting the output of my two functions to be accepted by the convolution function. Any help is appreciated getting this to work. I get the following when I use conv: Invalid data type. First and second arguments must be numeric or logical. I am familiar with matlab and can do the plots and other aspects once I get the function working. Thank you in advance for any help. I attached my code below:
t = -5:10; syms n x1 = symsum(dirac(t-8.*n),n,0,5); h1 = exp(-t).*heaviside(t); H1 = h1.'; Yt = conv(x1,h1);
My two functions are: x(t)=Sum(from 0-5) dirac(t-8n) h(t)=e^(-t)*u(t)
where u(t) is the step function
  2 Comments
Image Analyst
Image Analyst on 23 Sep 2018
Why are you using symbolic variables? Can't you just use numerical values with actual values for the elements?
Andrew Cunningham
Andrew Cunningham on 23 Sep 2018
I have “syms n” because it is needed in order to use the symsum to do summation. Cause n is also only from 0 to 5 while the time plot needs to be larger to plot the convolution of the two functions

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Accepted Answer

Viren Gupta
Viren Gupta on 27 Sep 2018
I tried relicating your code. x1 is of type sym. You can convert x1 into numeric type using double(x1). That should solve the error. 'h1' is already a numeric type variable
  1 Comment
Andrew Cunningham
Andrew Cunningham on 27 Sep 2018
Awesome thanks! I checked it out and that works. I solved it another way though and used ~isfinite(array) which turned the array into finite values. The only values in the array were infinity and 0 so I lost no data in doing it this way. Thank you for the help!

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