# datacube.utils.geometry.get_scale_at_point¶

datacube.utils.geometry.get_scale_at_point(pt, tr, r=None)[source]

Given an arbitrary locally linear transform estimate scale change around a point.

1. Approximate Y = tr(X) as Y = A*X+t in the neighbourhood of pt, for X,Y in R2

2. Extract scale components of A

pt - estimate transform around this point r - radius around the point (default 1)

tr - List((x,y)) -> List((x,y))

takes list of 2-d points on input and outputs same length list of 2d on output

Returns (sx, sy), where sx > 0, sy > 0