我在 overleaf 中有一段文本，底部有一个公式，但我不知道为什么 overleaf 编译失败。它说我缺少一个 $ 或 {，但我没有发现那里有什么问题。Overightharp 是我导入的一个包，它运行良好，所以这不是问题所在。这里出了什么问题？
The stiffness matrix $\bf{K}$ of the physical reservoir
is a function of $\overrightharp{x}$, where
$\overrightharp{x}=\[x_1(t), x_(t),...,x_D(t)\]$
is a collection of all displacements for $D$
masses/nodes/neurons. Since the mass displacements
vary as a function of time, the stiffness matrix
dies as well. Consequently, the system's eigenvalues
and eigenfrequencies vary as a function of time. Using
the discretized time-scale $m=1,2,3,...,M$ with time-step
$dt$, the system's eigenvalues $\overrightharp{\lambda}(m)$
and eigenfrequencies $\overrightharp{\omega}(m)$ are found
analytically for each time step by solving the by solving the
Quadratic Eigenvalue Problem (QEP) shown below, where
$\overrightharp{v}(m)$ are the eigenvectors at each each
time-step $m$. There are a total of $2D$ eigenvalues, unlike
traditional eigenvalue problems where there are $D$ eigenvalues \cite{QEP}.
\begin{equation}
\left(\bf{M} \overrightharp{\lambda^2}(m)+\bf{C}\overrightharp{\lambda}(m)
+\bf{K}\right)\overrightharp{v}(m) = 0
\end{equation}
答案1
的参数\overrightharp以文本模式排版（见https://mirror.las.iastate.edu/tex-archive/macros/latex/contrib/harpoon/harpoon.pdf)，因此使用$\overrightharp{\lambda}$不起作用，因为这就像\lambda在文本中书写一样。相反，您可以使用\overrightharp{$\lambda$}。
例如更改$\overrightharp{\lambda}(m)$为\overrightharp{$\lambda$}$(m)$。
编辑：这可行，但鱼叉会有点丑。accents包可能更好用，见https://tex.stackexchange.com/a/426353/319442。