Matrix-Based Minimization

LeastSquares solve an exact or approximate least-squares problem

PseudoInverse pseudoinverse of a square or rectangular matrix

Norm matrix and vector p-norms

QRDecomposition  ▪  SingularValueDecomposition

Fit find a linear least-squares fit to a symbolic basis

FindFit find a general nonlinear least-squares fit

LinearProgramming solve linear programming problems