Standard Tools

The most operations needed are standard operations such as rotating, sorting and clipping data. Those standard functions are already implemented in the toolbox. To mark all programs of the graph toolbox, the program names always begin with gr_. To make the tools usable, all tools should lie within the path.

gr_copy

This is the identical mapping of the point sets. It's possible to spcify sets, that must not be printed. (for further informtionn see chapter: Standard Parameters)

gr_analyze

Checks the number of sets, the number of points per set, the dimension of the points, the data value range. gr_analyze can be used as a fast way of examining the data.

gr_transform

Performs all possible transformations such as translations, rotations, reflection, shearing and perspective. Either each translation or scaling factor is specified or a matrix is given (in an extra file or as a first set) to define the view.

gr_rotate

Rotations of the points. A center of rotation can be specified.

gr_scale

This program scales the data set. It is possible to specify a range for one coordinate. The sets will be scaled to the given size, keeping the same ratio.

gr_sort

sorts the points in the set. The set can be sorted upwards or downwards, using any coordinate for comparison.

gr_spline

Cubic spline using the point data as control points. The knots can be specified in an extra file or the distribution of the knots can be specified (equal distance distribution, arclength distribution, delta x distribution).

gr_curvature

calculates the curvature of a polygon.

gr_reduce

Removing points from the set printing only every 2nd point (2 is the default, but any other number can be specified).

gr_plane

printing only the x or y or any specified coordinate plane. More than one plane can be specified and the order of the coordinates will be given by the user.

gr_merge

removing the set separators.

gr_split

Splitting a set into two halfs or after a certain number of points. (Works as an opposite of gr_merge.)

gr_del_double

Deletes points that are equal or within a specified epsilon neighborhood. Only points that are neighboured in the file are tested.

gr_del_point

Delete all points that lay within an interval or an epsilon box.

gr_del_empty_sets

All the empty sets will be removed.

gr_invert

inverts the order of the points in the set.

gr_roll

rolls the coordinats in clockwise direction: For a 3D data set, that would mean, the old x-coordinate becomes the new y-coordinate, while the old y-coordinate will be printed out as new z coordinate and the old z value will become the new x-value.

gr_bspline

Use the input points as control polygon for a bspline.

gr_nurbs

Use the input points as control polygon for Non Uniform Rational BSplines (nurbs)

gr_lift

calculates the volume of curves. If it is used for more than one set, the volume of every second curve is subtracted from the volume of the first curves.

gr_merge

adjacent This routine tries to fit different sets with the same start and endpoints together to a set.

gr_trig

calculates a Delaunay-triangulation out of a set of points.

gr_border

the border of a structured set will be taken. The first and last set will be printed and the first and last point of any other set.

gr_interior

the interior of a structured set will be taken. The interior of a structured set is defined as everything but the points printed by gr_border.

gr_uv2vu

changing the orientation of a number of structured sets. All input points must have the same number of points. The output will have as many sets as the number of points per set of the input data. Each set of the output data will have as many point as the number of sets from the input data.

For more detailed information on the modules see the -h online help on each gr_ tool.