Syntax problem in creating a function which takes a vector as an argument

r_1 = 0.84 - 0.29i;

r_2 = 0.84 + 0.29i;

c = 4.55;

t = [2:1:50];

y(t) = k_1*r_1^t + k_2*r_2^t + c;

function out = t

out = [y(t)];

end

Hey! I have a syntax problem with my function:

I am trying to write a code which takes a vector [t_1,..,t_n] as an argument and returns a vector [y(t_1),...,y(t_n)]. Here you can see my function for now and the parameters which the function should have. How I should write the working code?

Answer 1

[Dyuman Joshi]

Use element-wise power - power, .^ and define the expression as an anonymous function -

r_1 = 0.84 - 0.29i;
r_2 = 0.84 + 0.29i;
c = 4.55;
t = 2:1:50;

%Sample values for example
k_1 = 1;
k_2 = 2;

y = @(t) k_1*r_1.^t + k_2*r_2.^t + c;
out = y(t)

out = 
  Columns 1 through 10

   6.4145 + 0.4872i   5.6923 + 0.5895i   4.9967 + 0.6056i   4.3984 + 0.5519i   3.9425 + 0.4489i   3.6491 + 0.3184i   3.5163 + 0.1803i   3.5248 + 0.0516i   3.6440 - 0.0558i   3.8375 - 0.1344i

  Columns 11 through 20

   4.0684 - 0.1818i   4.3037 - 0.1993i   4.5165 - 0.1912i   4.6882 - 0.1639i   4.8086 - 0.1243i   4.8754 - 0.0794i   4.8924 - 0.0352i   4.8683 + 0.0035i   4.8143 + 0.0337i   4.7427 + 0.0539i

  Columns 21 through 30

   4.6650 + 0.0639i   4.5910 + 0.0648i   4.5281 + 0.0584i   4.4808 + 0.0469i   4.4511 + 0.0327i   4.4384 + 0.0179i   4.4407 + 0.0043i   4.4545 - 0.0070i   4.4758 - 0.0151i   4.5008 - 0.0198i

  Columns 31 through 40

   4.5260 - 0.0214i   4.5484 - 0.0203i   4.5664 - 0.0172i   4.5787 - 0.0129i   4.5853 - 0.0080i   4.5867 - 0.0033i   4.5837 + 0.0007i   4.5777 + 0.0039i   4.5699 + 0.0059i   4.5615 + 0.0069i

  Columns 41 through 49

   4.5537 + 0.0069i   4.5471 + 0.0062i   4.5422 + 0.0049i   4.5392 + 0.0034i   4.5380 + 0.0018i   4.5384 + 0.0003i   4.5399 - 0.0009i   4.5423 - 0.0017i   4.5450 - 0.0022i

[Jenni]

Excellent! Using the - power, .^ and defining the expression as an anonymous function was very helpful idea! Thank you!