Notations and Symbols Cheatsheet
f :𝒳→𝒴 The function f maps from the space 𝒳 to the space 𝒴
x ∈ ℝd x is a vector in the d-dimensional real valued vector space ( ℝd )
D ∈ ℝn×d D is a real-valued matrix with n rows and d columns
D⋅k All rows of the kth column of matrix D
Di⋅ All columns of the ith row of matrix D
∥⋅∥ The default norm (L 2/Euclidian) or any norm, depending on the context
|⋅| The L1 norm
∥⋅∥p The Lp-norm, where p ≥ 1
t r () Trace function
∇f Gradient of f
δ
f (x) Partial derivative of f subject to xk
δ xk
1 The constant one vector (has as many ones as there are dimensions)
iff if and only if
f :𝒳→𝒴 The function f maps from the space 𝒳 to the space 𝒴
x ∈ ℝd x is a vector in the d-dimensional real valued vector space ( ℝd )
D ∈ ℝn×d D is a real-valued matrix with n rows and d columns
D⋅k All rows of the kth column of matrix D
Di⋅ All columns of the ith row of matrix D
∥⋅∥ The default norm (L 2/Euclidian) or any norm, depending on the context
|⋅| The L1 norm
∥⋅∥p The Lp-norm, where p ≥ 1
t r () Trace function
∇f Gradient of f
δ
f (x) Partial derivative of f subject to xk
δ xk
1 The constant one vector (has as many ones as there are dimensions)
iff if and only if