近期即将分享的一些代码待续……

$$
0 \xleftarrow [\zeta]{} F \times \Delta (n - 1)
\xrightarrow {\partial_0 \alpha(b)} E^{\partial_0 b}
$$

$$\int^{b}_{a}f(x)\,dx
=-\int^{a}_{b}f(x)\,dx$$

$$\int^{b}_{a}f(x)\,dx=-\int^{a}_{b}f(x)\,dx\tag{1.1.1}$$

$$\int^{b}_{a}f(x)\,dx=F(b)-F(a)\tag{1.1.2}$$

$$
A=\left(\begin{array}{c|c}
a_{11} & a_{12} \\ \hline
a_{21} & a_{22}
\end{array}\right)
\tag{1.1.3}
$$

$$
\left(
\begin{array}{c@{}c@{}}
\begin{array}{|cc|}\hline
a_{11} & a_{12} \\
a_{21} & a_{22} \\\hline
\end{array} & 0  \\
0 & \begin{array}{|ccc|}\hline
b_{11} & b_{12} & b_{13}\\
b_{21} & b_{22} & b_{23}\\
b_{31} & b_{32} & b_{33}\\\hline
\end{array}\\
\end{array}\right)
\tag{1.1.4}
$$

$$
\left(
\begin{array}{c@{}c}
\begin{array}{>{\columncolor[gray]{.8}}c>{\columncolor[gray]{.8}}c}
a_{11} & a_{12} \\
a_{21} & a_{22} \\
\end{array} & 0  \\
0 & \begin{array}{>{\color{white}}c>{\color{white}}c>{\color{white}}c}
\rowcolor{blue}b_{11} & b_{12} & b_{13}\\
\rowcolor{blue}b_{21} & b_{22} & b_{23}\\
\rowcolor{blue}b_{31} & b_{32} & b_{33}\\
\end{array}\\
\end{array}\right)
\tag{1.1.5}
$$

$$
\begin{alignat}{2}
A_{1} & =B_{1}B_{2}\quad & A_{3} & =B_{1}\\
A_{2} & =B_{3} & A_{3}A_{4} & =B_{4}
\end{alignat}\tag{1.1.6}
$$

We spacify aan agent behaviour rule,
$$
y_t=\beta\mathbb{E}y_{t+1}+x_t
$$

from fastLm.cpp:23:
   ../inst/include/Eigen/src/Core/CoreEvaluators.h: In instantiation of 'struct Eigen::internal::evaluator<Eigen::Block<const Eigen::Matrix<double, -1, -1, 1, -1, -1>, -1, -1, false> >':
   ../inst/include/Eigen/src/Core/CoreEvaluators.h:99:8:   required from 'struct Eigen::internal::evaluator<const Eigen::Block<const Eigen::Matrix<double, -1, -1, 1, -1, -1>, -1, -1, false> >'
   ../inst/include/Eigen/src/Core/CoreEvaluators.h:681:51:   required from 'struct Eigen::internal::binary_evaluator<Eigen::CwiseBinaryOp<Eigen::internal::scalar_product_op<double, double>, const Eigen::CwiseNullaryOp<Eigen::internal::scalar_constant_op<double>, const Eigen::Matrix<double, -1, -1, 1, -1, -1> >, const Eigen::Block<const Eigen::Matrix<double, -1, -1, 1, -1, -1>, -1, -1, false> >, Eigen::internal::IndexBased, Eigen::internal::IndexBased, double, double>'
   ../inst/include/Eigen/src/Core/CoreEvaluators.h:665:8:   required from 'struct Eigen::internal::evaluator<Eigen::CwiseBinaryOp<Eigen::internal::scalar_product_op<double, double>, const Eigen::CwiseNullaryOp<Eigen::internal::scalar_constant_op<double>, const Eigen::Matrix<double, -1, -1, 1, -1, -1> >, const Eigen::Block<const Eigen::Matrix<double, -1, -1, 1, -1, -1>, -1, -1, false> > >'
..   ../inst/include/Eigen/src/Core/AssignEvaluator.h:730:20:   required from 'void Eigen::internal::call_dense_assignment_loop(DstXprType&, const SrcXprType&, const Functor&) [with DstXprType = Eigen::Block<Eigen::Matrix<double, -1, -1, 0, -1, 1>, -1, -1, true>; SrcXprType = Eigen::CwiseBinaryOp<Eigen::internal::scalar_product_op<double, double>, const Eigen::CwiseNullaryOp<Eigen::internal::scalar_constant_op<double>, const Eigen::Matrix<double, -1, -1, 1, -1, -1> >, const Eigen::Block<const Eigen::Matrix<double, -1, -1, 1, -1, -1>, -1, -1, false> >; Functor = Eigen::internal::sub_assign_op<double, double>]'
   ../inst/include/Eigen/src/Core/AssignEvaluator.h:879:31:   required from 'static void Eigen::internal::Assignment<DstXprType, SrcXprType, Functor, Eigen::internal::Dense2Dense, Weak>::run(DstXprType&, const SrcXprType&, const Functor&) [with DstXprType = Eigen::Block<Eigen::Matrix<double, -1, -1, 0, -1, 1>, -1, -1, true>; SrcXprType = Eigen::CwiseBinaryOp<Eigen::internal::scalar_product_op<double, double>, const Eigen::CwiseNullaryOp<Eigen::internal::scalar_constant_op<double>, const Eigen::Matrix<double, -1, -1, 1, -1, -1> >, const Eigen::Block<const Eigen::Matrix<double, -1, -1, 1, -1, -1>, -1, -1, false> >; Functor = Eigen::internal::sub_assign_op<double, double>; Weak = void]'
   ../inst/include/Eigen/src/Core/AssignEvaluator.h:836:49:   [ skipping 15 instantiation contexts, use -ftemplate-backtrace-limit=0 to disable ]