Solving an equation with 2 known arrays

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I'm trying to solve equation with 1 variable (k) but 2 vectors (x and t).
I need to get an array of answers for k, such as (k[i] = eqn(t[i],x[i]).
This is what I wrote:
t = [28.35 53.34 85.39 132.7];
x = linspace(0.01,0.04,4);
k = sym ('k',[1 4]);
eqn = T-Ti==(2*q*sqrt((t.*k)/(c*p*pi))./k)*exp(((-x.^2)*c*p)./(4*k.*t))-((q*x)./k)*erfc(x/(2*sqrt((t.*k)/(c*p))));
solk = solve(eqn,k);
solk.k1
solk.k2
solk.k3
solk.k4
and of course it doesn't work.
How do I fix it?

Answers (1)

Sreeranj Jayadevan
Sreeranj Jayadevan on 30 Dec 2020
Your code is working as expected. I was able to execute the same when a different equation was used. Check if the equation you are using contain dimensional mismatches.
The following code works:
x=sym('x', [1 4]);
y=[1 2 3 4];
z=[2 3 4 5];
sol=solve(x.*y+z+1==0,x); % You can change this equation
sol.x1
sol.x2
sol.x3
sol.x4
% Converting it into an array of type double
temp=struct2cell(sol);
sol_arr=double([temp{:}]);
"sol_arr" returns the array of answers that you require.

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