easy question : why i get NaN here ?
1 view (last 30 days)
Show older comments
yahya elyan
on 30 May 2020
Answered: Walter Roberson
on 31 May 2020
>> u=1/(1+limit(K/(w*(((J*w+b)*(L*w+R))+K^2)),w,0))
or
>> limit(K/(w*(((J*w+b)*(L*w+R))+K^2)),w,0)
6 Comments
Accepted Answer
yahya elyan
on 30 May 2020
2 Comments
madhan ravi
on 30 May 2020
Edited: madhan ravi
on 30 May 2020
It is solved but do you know the reason for NaN xD? Because your original question asks “why...?”
More Answers (1)
Walter Roberson
on 31 May 2020
J = 0.01;
b = 0.0737;
K = 0.072;
R = 1.17;
L = 0.024;
syms w
temp = K/(w*(((J*w+b)*(L*w+R))+K^2));
tempc = collect(temp, w);
disp(tempc)
ans =
120000/(400*w^3 + 22448*w^2 + 152355*w)
Examing this, we see that as w approaches 0, the controlling expression would be the 152355*w part -- the w^3 and w^2 parts would vanish compared to the w component. So the limit of temp as w goes to 0 would be like
limit( (120000/152355)/w, w, 0)
When w approaches from the right, that is positive divided by +0, which is +infinity
When w approaches from the left, that is positive divided by -0, which is -infinity
Therefore the left and right limits are different, so the limit is not defined.
0 Comments
See Also
Categories
Find more on Calculus in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!