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Matrix multiplication error using '.*'

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AJ Woodson
AJ Woodson on 17 Nov 2020
Answered: Andrei Bobrov on 17 Nov 2020
%so this is my simply code
r = randi(100,66);
t = (0:1/55:1);
e = exp(2*pi*i*13*t);
t = r.*e % this gives me error why is it and how can fix
  4 Comments
VBBV
VBBV on 17 Nov 2020
@woodson then you have to divide t into 66. as
%if true
t = 0:1/65:1;
To get what you want.

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Answers (3)

madhan ravi
madhan ravi on 17 Nov 2020
t = linspace(0, 1, 66);
  1 Comment
AJ Woodson
AJ Woodson on 17 Nov 2020
Thank you for the response ideally r is signl and e is a Doppler shift so matrix size would be 66x66 to explain further it would be like x = [2 4 5 2 3 5 6] x.*5 and output would be a x = [10, 20, 25 etc. ideal e in my case is just a scalar if I'm making myself clear where in the example r = x and e = 5

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Walter Roberson
Walter Roberson on 17 Nov 2020
randi(100,66) creates a 66 x 66 matrix of values 1 to 100.
0:1/55:1 is length 56.
When you .* a 66x66 matrix and a 1x56 matrix then what size of output are you expecting?
  1 Comment
AJ Woodson
AJ Woodson on 17 Nov 2020
Thank you for the response ideally r is signl and e is a Doppler shift so matrix size would be 66x66 to explain further it would be like x = [2 4 5 2 3 5 6] x.*5 and output would be a x = [10, 20, 25 etc. ideal e in my case is just a scalar if I'm making myself clear where in the example r = x and e = 5

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Andrei Bobrov
Andrei Bobrov on 17 Nov 2020
r = randi(100,66);
t = reshape(0:1/55:1,1,1,[]);
e = exp(2*pi*i*13*t);
t = r.*e;

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