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How To use Fréchet View
File / Open

open an input file and display the correspondig Freespace diagram. See File Formats for supported files.

play with parameter Epsilon and watch the FreeSpace diagram change.
 select an algorithm using the panel on the lower left part of the screen:
Curve Algorithm
computes the classical Fréchet Distance for polygonal curves. The answer to the decision problem ("is delta_F <= epsilon ?") is displayed in realtime.
The resulting feasible path is shown as a yellow line inside the freespace diagram. The path may wrap at the right edge of the diagram and continue at the left edge.
Move the mouse pointer over an edge (or a diagonal) to highlight the correspoding parts of the curves.
Show Bounds displays reachable intervals as dotted lines.
Separate Curves moves the input curves apart.
(Optimise und Approximate see below).
Polygon Algorithm
computes the Fréchet distance for simple polygons (i.e. polygons without holes, and without selfintersections).
Decide computes the answer to the decision problem. If successful, the resulting feasible path is shown in the Freespace diagram.
Optimize computes the Fréchet distance (i.e. the smallest possible epsilon) using binary search on a set of critical values.
Approximate computes an approximation result (may sometimes be faster).
kFréchet Algorithm
computes the parameter k for the kFrechet distance.

the "Greedy" result is shown immediately. Lower and upper bounds for k are shown.

click "BruteForce" to compute the exact result; stop the computation if it takes too long.
Connected components are indicated by color.
Click "Show Bounds" to project components to the x and yaxes. These projected intervals are the basis for the kFréchet algorithms.
Print and Save
Curves and the FreeSpace diagram can be printed, or saved to disk as a PDF file. (note: saving to an SVG file is available, but may not be accurate. Do prefer PDF).
Command Line
There is a Command Line Interface with some more options.
Updated