Gradient pattern analysis (GPA) is a geometric computing method for characterizing geometrical bilateral symmetry breaking of an ensemble of symmetric vectors regularly distributed in a square lattice. Usually, the lattice of vectors represent the first-order gradient of a scalar field, here an M x M square amplitude matrix. An important property of the gradient representation is the following: A given M x M matrix where all amplitudes are different results in an M x M gradient lattice containing N V = M 2 {\displaystyle N_{V}=M^{2}} asymmetric vectors. As each vector can be characterized by its norm and phase, variations in the M 2 {\displaystyle M^{2}} amplitudes can modify the respective M 2 {\displaystyle M^{2}} gradient pattern.
The original concept of GPA was introduced by Rosa, Sharma and Valdivia in 1999. Usually GPA is applied for spatio-temporal pattern analysis in physics and environmental sciences operating on time-series and digital images.