DTW

class dtw.DTW(obj)

Bases: object

The results of an alignment operation.

Objects of class DTW contain alignments computed by the [dtw()] function.

Attributes:

  • distance the minimum global distance computed, not normalized.

  • normalizedDistance distance computed, normalized for path length, if normalization is known for chosen step pattern.

  • N,M query and reference length

  • call the function call that created the object

  • index1 matched elements: indices in x

  • index2 corresponding mapped indices in y

  • stepPattern the stepPattern object used for the computation

  • jmin last element of reference matched, if open_end=True

  • directionMatrix if keep_internals=True, the directions of steps that would be taken at each alignment pair (integers indexing production rules in the chosen step pattern)

  • stepsTaken the list of steps taken from the beginning to the end of the alignment (integers indexing chosen step pattern)

  • index1s, index2s same as index1/2, excluding intermediate steps for multi-step patterns like [asymmetricP05()]

  • costMatrix if keep_internals=True, the cumulative cost matrix

  • query, reference if keep_internals=True and passed as the x and y arguments, the query and reference timeseries.

Methods Summary

plot([type])

Plotting of dynamic time warp results

Methods Documentation

plot(type='alignment', **kwargs)

Plotting of dynamic time warp results

Methods for plotting dynamic time warp alignment objects returned by [dtw()].

Details

dtwPlot displays alignment contained in dtw objects.

Various plotting styles are available, passing strings to the type argument (may be abbreviated):

  • alignment plots the warping curve in d;

  • twoway plots a point-by-point comparison, with matching lines; see [dtwPlotTwoWay()];

  • threeway vis-a-vis inspection of the timeseries and their warping curve; see [dtwPlotThreeWay()];

  • density displays the cumulative cost landscape with the warping path overimposed; see [dtwPlotDensity()]

Additional parameters are passed to the plotting functions: use with care.

Parameters:

  • x – dtw object, usually result of call to [dtw()]

  • d – dtw object, usually result of call to [dtw()]

  • xlab – label for the query axis

  • ylab – label for the reference axis

  • type – general style for the plot, see below

  • plot_type – type of line to be drawn, used as the type argument in the underlying plot call

  • ... – additional arguments, passed to plotting functions