solving trascendental equations, proper setting
조회 수: 1 (최근 30일)
이전 댓글 표시
Hello everybody,
I'd like to solve for y = y(x) the following equation
d log( y ) / d x + y = 1 + f
with f = f(x).
f is a 1D numerically known array, I don't know its nalytical form.
I cannot set properly solve or fzero.
Can you help me, please?
Patrizio
댓글 수: 0
채택된 답변
Ameer Hamza
2020년 6월 14일
편집: Ameer Hamza
2020년 6월 14일
This is a differential equation and you can use symbolic toolbox to find an anayltical solution
syms y(x) f
eq = diff(log(y), x) + y == 1 + f;
sol = dsolve(eq);
Result
>> sol
sol =
(exp((C1 + x)*(f + 1))*(f + 1))/(exp((C1 + x)*(f + 1)) + 1)
f + 1
Following shows how to get a numerical solution using ode45
syms y(x) f
eq = diff(log(y), x) + y == 1 + f;
sol = dsolve(eq);
odeFun = matlabFunction(odeToVectorField(eq), 'Vars', {'t', 'Y', 'f'});
tspan = [0 10]; % time span for numerical solution
ic = 1; % initial condition: y(0)==1
fv = 1; % numerical solution for f=1
[t, y] = ode45(@(t, y) odeFun(t, y, fv), tspan, ic);
plot(t, y);
댓글 수: 7
Ameer Hamza
2020년 6월 17일
I am glad that it worked for your case, and you got the results. Good luck with your research.
추가 답변 (0개)
참고 항목
카테고리
Help Center 및 File Exchange에서 Calculus에 대해 자세히 알아보기
제품
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!