ECD                     ECD algorithm for estimating the envelope
                        subspace
EEG                     Electroencephalography (EEG) dataset for
                        alcoholism study.
EnvMU                   Estimate envelope subspace basis
FGfun                   The Objective function and its gradient
MenvU_sim               Generate sample estimator of 'M' and 'U'
OptManiMulitBallGBB     Line search algorithm for optimization on
                        manifold
OptStiefelGBB           Optimization on Stiefel manifold (GBB)
OptimballGBB1D          Estimate the envelope subspace (Feasi 1D)
PMSE                    Predictions and Mean squared error for tensor
                        predictor regression (TPR).
TPR.fit                 Tensor predictor regression
TPR_sim                 Generate simulation data for tensor predictor
                        regression (TPR)
TRES-package            Tensor Regression with Envelope Structure and
                        Three Generic Envelope Estimation Approaches
TRR.fit                 Tensor response regression
TRR_sim                 Generate simulation data for tensor response
                        regression (TRR)
TensEnv_dim             Envelope dimension selection for tensor
                        response regression (TRR)
TensPLS_cv2d3d          Envelope dimension by cross-validation for
                        tensor predictor regression (TPR).
Tenv_Pval               The p-value and standard error of each element
                        in the estimator of the tensor response
                        regression (TRR) coefficient
ballGBB1D_bic           Envelope dimension selection based on 1D-BIC
bat                     Bat simulated data
fun1D                   The 1D objective function and its gradient
get_ini1D               Initial value for 1D algorithm
kroncov                 The covariance estimation of a tensor random
                        variable
manifold1D              Estimate the envelope subspace (ManifoldOptim
                        1D)
manifoldFG              Estimate the envelope subspace (ManifoldOptim)
plot.Tenv               Plot coefficients and p-value for Tenv object.
predict.Tenv            Predict method for Tenv object.
square                  Square simulated data
std_err                 Extracting the standard error.
subspace                The distance between two subspaces.
summary.Tenv            Summarize method for Tenv object.
ttt                     Inner product of two tensors
