twdtw (version 1.0-1)

plot_cost_matrix: Plot TWDTW cost matrix

Description

This function visualizes the Time-Weighted Dynamic Time Warping cost matrix.

Usage

plot_cost_matrix(x, ...)

Value

An image plot of the TWDTW cost matrix. The x-axis represents the time series x, and the y-axis represents the time series y. The cost matrix is color-coded, with darker shades indicating higher costs and lighter shades indicating lower costs. No object is returned by this function; the plot is directly outputted to the active device.

Arguments

x

An object of class 'twdtw' including internal data.

...

Additional arguments passed to image.

Examples

# Create a time series
n <- 23
t <- seq(0, pi, length.out = n)
d <- seq(as.Date('2020-09-01'), length.out = n, by = "15 day")

x <- data.frame(time = d,      v1 = sin(t)*2 + runif(n))

# shift time by 30 days
y <- data.frame(time = d + 30, v1 = sin(t)*2 + runif(n))

plot(x, type = "l", xlim = range(c(d, d + 5)))
lines(y, col = "red")

# Call twdtw using "output = 'internals'
twdtw_obj <- twdtw(x, y,
       cycle_length = 'year',
       time_scale = 'day',
       time_weight = c(steepness = 0.1, midpoint = 50), output = 'internals')

plot_cost_matrix(twdtw_obj)