MATLAB has a built-in routine called fzero that approximates roots of functions. (Function value at -2.61092 is 0.74278-0.30449i.)Ĭheck function or try again with a different starting value. Example Illustrating the Use of MATLABs fzero Routine.
FZERO MATLAB HOW TO
Any ideas on how to procede?Įxiting fzero: aborting search for an interval containing a sign changeīecause complex function value encountered during search.
But I don't have much experience with solving this in MATLAB and I guess I have a silly mistake somewhere. We write step by step program to solve the following questions. Solving an Equation Numerically using fzero Matlab has a collection of tools for finding approximate solutions but well focus on just one, thats the fzero command. This command takes inputs function f(x) and an initial guess x0 to the root. Points where the function touches, but does not cross, the x-axis are not. This is a somewhat well-behaved problem in Economics and the solution we are looking indeed exists and the algorithm I tried to implement is guaranteed to work. Introduction : fzero matlab command is used to find the root of an equation f(x)0. The fzero command defines a zero as a point where the function crosses the x-axis. But for indexes it just returns NaN and exits without finding the root. When I run this code, for some indexes $i$, it runs fine and fzero can find the solution. New_c = A*k_grid.^alpha + (1-delta)*k_grid - new_k New_k(i) = fzero(euler, k_grid(i)) % What's a good guess for fzero?
N_grid = 1000 % Number of points for capitalĬ_handle = interp1(k_grid, c0, k_tomorrow, 'linear', 'extrap') Įuler = (1/((1-delta)* k_grid(i) + A * k_grid(i)^alpha - k_tomorrow)) - beta*(1-delta + alpha*A*k_tomorrow^(alpha - 1))/c_handle(k_prime) MATLAB adds capability to search for an interval with a sign change.ContentsSeeking a sign change.MathWorks additionAn exampleSeeking a sign change. Here, k is fixed and c(k) was defined through the ```interp1''' function in Matlab. I am solving a problem in my Macroeconomics class.