# Canonical transformations

1. Apr 12, 2012

### zheng89120

Why is it that only Canonical transformations preserve the Hamilton's equations? Or what makes non-canonical transformations not preserve the Hamilton's equations?

2. Apr 12, 2012

### Dougy81

But that is the definition of canonical transformation that they preserve the Hamilton's equation. Whatever transformation of coordinates you find that preserves Hamilton's equation is a canonical transformation.