Rescale Methods

Rescale methods define ways of rescaling a trace to match a summary. They are defined to be subtypes of RescaleMethod.

The rescale method itself is defined by extending rescalesinglevariable! for the new type. For example:

struct RescaleMaxChangeMin <: RescaleMethod end
function rescalesinglevariable!(x::AbstractVector,y::Real,::RescaleMaxChangeMin)
    rescale = y/maximum(x)
    for i in eachindex(x)
        @inbounds x[i] *= rescale
    end
    nothing
end

is the implementation for RescaleMaxChangeMin.

The rescaletrace! function will call rescalesinglevariable! on each variable in a trace in turn, it takes a Tuple of RescaleMethods which allows for different rescales for different variables.

Available Methods

HistoricalStormTraceSimulation.RescaleIdentity — Type

RescaleIdentity()

A rescale type to represent the identity rescale.

source

HistoricalStormTraceSimulation.RescaleMaxChangeMin — Type

RescaleMaxChangeMin()

Linear rescale to adjust the maximum of the new trace to equal the summary value.

Given a trace variable series $y_j$, and summary value $x_j$, the new trace $\tilde{y}_j$ is constructed using the following rule, $\forall t\in T_y$:

$\tilde y_j(t) = \frac{x_j}{\max\limits_{t\in T_y}y_j(t)}y_j(t).$

source

HistoricalStormTraceSimulation.RescaleMaxPreserveMin — Type

RescaleMaxPreserveMin()

Linear rescale to adjust the maximum of the new trace to equal the summary value whilst preserving the minimum.

Given a trace variable series $y_j$, and summary value $x_j$, the new trace $\tilde{y}_j$ is constructed using the following rule, $\forall t\in T_y$:

$\tilde y_j(t) = \frac{x_j-\min\limits_{t\in T_y} y_j(t)}{\max\limits_{t\in T_y}y_j(t)-\min\limits_{t\in T_y} y_j(t)} \left(y_j(t)-\min\limits_{t\in T_y} y_j(t)\right) + \min\limits_{t\in T_y} y_j(t).$

This only works if the new maximum $x_j$ satisfies $x_j>\min\limits_{t\in T_y} y_j(t)$. The formula is $\forall t\in T_y$. If this condition is not satisfied, a warning will be displayed.

source

HistoricalStormTraceSimulation.RescaleMean — Type

RescaleMean()

Additive rescaling to match the mean of the trace to the summary value.

Given a trace variable series $y_j$, and summary value $x_j$, the new trace

$\tilde y_j(t) = y_j(t) - \overline{y_j} + x_j$

where $\overline{y_j} = \frac{1}{|T_y|} \sum_{t\in T_y}y_j(t)$.

source

HistoricalStormTraceSimulation.RescaleMeanCircularDeg — Type

RescaleMeanCircularDeg()

Rescale the angular mean assuming data is in degrees.

Given a trace variable series $y_j$, and summary value $x_j$, the new trace

$\tilde y_j(t) = y_j(t) - \overline{y_j} + x_j$

where $\overline{y_j} = \arg\left(\frac{1}{|T_y|} \sum_{t\in T_y}\exp\{i y_j(t)\}\right)$.

source