I'm trying to create a block diagonal matrix with labeled blocks as shown in the images below:
I have tried:
\documentclass{article}
\usepackage{amsmath}
\begin{document}
\begin{equation}
\begin{bmatrix}
\mathbf{D} & & & \textbf{\Huge 0} \\
& \mathbf{S}_1\\
& & \ddots \\
\textbf{\Huge0}& & & \mathbf{S}_r\\
\end{bmatrix}
\end{equation}
\end{document}
The location of the zeros, however, is not well aligned.