矩阵微积分 Matrix calculus，附录，对矩阵和向量求导D 1. GRADIENT, DIRECTIONAL DERIVATIVE, TAYLOR SERIES
551
VxI
2(X)△|vax
(X)Vbx2|∈K×L×KxL
dg(x
V
6g(X)
aa(X)
OKI
aXK2
OXKL
(1962
VV
X
五×1×L×H×L
R
9(X)
where the gradient V is with respect to matrix X
Gradient of vector-
