# Non-Linear Pattern Deformation

By default, PatMax requires that each boundary point in the instance of a pattern found in a run-time image closely correspond to a boundary point in the trained pattern. PatMax can match and identify any change that can be described by a linear geometric transformation (assuming you specify the appropriate degrees of freedom and zones).

When patterns exhibit nonlinear geometric changes, PatMax can fail to find them, or it can return a low score or inaccurate location information. There are two ways PatMax can work with patterns that exhibit nonlinear geometric change.

- In cases with a small amount of deformation, you can specify a nonzero elasticity value (in pixels) that specifies how much non-linear deformation PatMax will tolerate.
- In cases with substantial deformation, can use the PatFlex algorithm to locate and match patterns and return information about the deformation of the found pattern instance.

See the following topics for more information: