Assigning values to variables after using isolate?

Question

Ananya Sahu 2020-6-19

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/551506-assigning-values-to-variables-after-using-isolate

回答： Devineni Aslesha 2020-6-22

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 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Devineni Aslesha 2020-6-22

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/551506-assigning-values-to-variables-after-using-isolate#answer_455527

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