use the align environment

Author: Carol-seven

vignettes/pen_est.Rmd

@@ -40,19 +40,19 @@ Consider the following setting:
 ## Sparse-Group Estimator
 
 
-\begin{gather}
+\begin{align}
 \hat{\Omega}(\lambda,\alpha,\gamma)
 = \operatorname*{arg\,min}_{\Omega \succ 0} \Bigl\{
 - \log\det(\Omega) + \operatorname{tr}(S\Omega)
-+ P_{\lambda,\alpha,\gamma}(\Omega) \Bigr\}, \\ \\
++ P_{\lambda,\alpha,\gamma}(\Omega) \Bigr\}, \\
 P_{\lambda,\alpha,\gamma}(\Omega)
 = \alpha P^\text{individual}_{\lambda,\gamma}(\Omega)
-+ (1-\alpha) P^\text{group}_{\lambda,\gamma}(\Omega), \\ \\
++ (1-\alpha) P^\text{group}_{\lambda,\gamma}(\Omega), \\
 P^\text{individual}_{\lambda,\gamma}(\Omega)
-= \sum_{i,j} p_{\lambda,\gamma}(\vert\omega_{ij}\vert), \\ \\
+= \sum_{i,j} p_{\lambda,\gamma}(\vert\omega_{ij}\vert), \\
 P^\text{group}_{\lambda,\gamma}(\Omega)
 = \sum_{g,g^\prime} p_{\lambda,\gamma}(\Vert\Omega_{gg^\prime}\Vert_F),
-\end{gather}
+\end{align}
 
 
 where: