prophys.transformations

Deterministic transformations: linear, polynomial, piecewise, decay, dose response, tables and periodic signals.

A Transform maps an expression to an expression and composes with Transform.then(). Bijective transforms also serve as bijectors of a TransformedDistribution.

Classes

Transform	Base class of deterministic transformations that map expressions to expressions.
FunctionTransform	Wrap a plain Expr -> Expr callable as a transform that is not bijective.
Linear	Elementwise linear map y = a * x + b, bijective for a != 0.
Affine	Affine map y = A @ x + b of a vector x, bijective for invertible A.
Polynomial	Elementwise polynomial y = sum_i coeffs[i] * x**i, lowest order first.
PiecewiseLinear	Piecewise linear curve through (knots[i], values[i]).
Decay	Exponential or power law decay with distance, typically composed after a distance primitive.
Logistic	Logistic dose response curve L / (1 + exp(-k * (x - x0))).
TableLookup1D	Linearly interpolated 1D lookup table, e.g. a wind turbine power curve.
TableLookup2D	Bilinearly interpolated 2D lookup table, e.g. sound power level over (wind speed, direction).
Phase	Wrap a continuous variable into [0, period), e.g. hours since start into hour of day.
Periodic	Learnable finite Fourier series for seasonal, diurnal or tidal signals.
ReturnPeriod	Convert an annual exceedance probability to a return period 1 / p and back.
RecurrenceRate	Convert a mean time between events to an event rate 1 / interval and back.