MATLAB Answers

Assigning values to variables after using isolate?

1 view (last 30 days)
Ananya Sahu
Ananya Sahu on 19 Jun 2020
Answered: Devineni Aslesha on 22 Jun 2020
Here is my code:
%% Model
syms M n D t r
eqn = M - (1 - 6/(pi^2)) * symsum((1/n^2 * exp((-D*n^2*pi^2*t)/(r^2))),n,0,Inf) == 0;
%% Variables
t = [0.50373, 43.2325, 86.72428, 129.74978, 173.8774, 216.69095];
M = [0.75233, 62.53212, 67.84044, 67.6522, 80.90417, 82.59832];
r = 130/(10^9);
Dsol = isolate(eqn, D)
disp(Dsol)
However, the output is just the solution to Dsol and not the actual array of Dsol values. How can I assign the values to t, M, and r to obtain an array for Dsol?

  0 Comments

Sign in to comment.

Answers (1)

Devineni Aslesha
Devineni Aslesha on 22 Jun 2020
In your code, check with the symsum function as it do not return the sum of the series((-D*n^2*pi^2*t)/(r^2))) with respect to the summation index n. You can use the subs function to get the actual array of Dsol values as shown below.
subs(rhs(Dsol),{t,M,r},{t1,M1,r1});
Here, t1 = [0.50373, 43.2325, 86.72428, 129.74978, 173.8774, 216.69095]
M1 = [0.75233, 62.53212, 67.84044, 67.6522, 80.90417, 82.59832] and
r1 = 130/(10^9);
For more information, refer Substitute Multiple Scalars with Arrays from this link

  0 Comments

Sign in to comment.

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!