Error when plotting in Octave

Question

In Octave 4.0.2 I have defined a function S as follows:

S = @(x) (Y(k)+((Y(k+1)-Y(k))/h(k)-(2*M(k)+M(k+1))*h(k)/6)*(x-X(k))+M(k)*(k-X(k))^2/2+(M(k+1)-M(k))*(x-X(k))^3/(6*h(k)))

When I call it to evaluate a number in the interval [X(k), X(k+1)] I get the result I expect, but when I try plotting it with the command:

fplot(S, [X(k), X(k+1)]); hold on;

I get the error "error: for A^b, A must be a square matrix. Use .^ for elementwise power."

What is going on?

Answer 1

好吧，我发现将函数传递给fplot时，它必须能够获取输入向量并返回输出向量。