## ransack

`ransack`
generates random points inside the mask.

`
ransack [-d] [-q] [-c<n>] [-r<n>] [-m<a>[u]] [-s<n>] [-e<n>] [-u<inunit>[,<outunit>]] [-p[+|-]<n>]
[-i<f>[<n>][u]] polygon_infile1 [polygon_infile2 ...] azel_outfile
`
The

`-c<n>`switch seeds the random number generator with integral seed

`<n>`.

The

`-r<n>`switch commands to generate

`<n>`random numbers.

`polygon_infile1 [polygon_infile2 ...]`are polygon files specifying the mask.

`azel_outfile`is the name of a file to which to write the random positions. In addition to recording the azimuth and elevation of each position,

`ransack`writes the id number of the polygon inside which the random position falls.

The algorithm is as follows.

`ransack`first selects randomly a polygon in the mask, with probability proportional to the product of the polygon's weight and area. It lassos that polygon with a circle that is intended to be a tight fit, but is not necessarily minimal. It generates a point randomly within the circle, tests whether the point lies inside the polygon, and keeps the point if it does.

`ransack`lassos polygons as needed, recording a lasso so that a lasso is computed only once for any polygon. If the desired number of random points exceeds the number of polygons in the mask, then

`ransack`starts by lassoing every polygon in the mask.

`ransack`is quite fast.

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