How to write the codes for this?

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i am trying to get the value for b.
where
t = [89;132;202;263;321;362;421;473;575;663]
n=10;
syms b
[b] = solve((1/b) + sum(log(t))/10 - 1.*sum(t.^b).*log(t)/(sum(t.^b))==0)
i tried this code to find 'b' but i am not getting the value of 'b'. How can i get the value for 'b'?

Accepted Answer

Ameer Hamza
Ameer Hamza on 23 Oct 2020
If you want to find value of 'b' for each value of 't' then try this
tv = [89;132;202;263;321;362;421;473;575;663];
syms b t
b_sol = solve((1/b) + sum(log(t))/10 - 1/(sum(t.^b)/10).*sum(t.^b).*log(t)==0, b);
b_vals = subs(b_sol, t, tv)
  5 Comments
Ameer Hamza
Ameer Hamza on 23 Oct 2020
You were also dividing the term in the denominator by 10. Try the following code
t = [89;132;202;263;321;362;421;473;575;663]
n=10;
syms b
b_sol = solve((1/b) + sum(log(t))/10 - 1/(sum(t.^b)).*sum((t.^b).*log(t))==0)
Result
b_sol =
2.0923855034345368572888674897445

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More Answers (1)

Walter Roberson
Walter Roberson on 23 Oct 2020
Your t is a vector.
[b] = solve((1/b) + sum(log(t))/10 - 1/(sum(t.^b)/10).*sum(t.^b).*log(t)==0)
You have log(t) there at the end, in a context that is not inside a sum() like the rest of the places you use t. Therefore you are generating a vector of equations, and you are asking solve() to find a single t that solves all of the equations simultaneously.
You need to re-check your last term. For example there is a numeric solution for
vpasolve((1/b) + sum(log(t))/10 - 1/(sum(t.^b)/10).*sum(t.^b.*log(t))==0, 0.02)

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