# plot::Group2d

Groups of 2D objects

### Use only in the MuPAD Notebook Interface.

This functionality does not run in MATLAB.

## Syntax

```plot::Group2d(`object2d1, object2d2, …`, <`a = amin .. amax`>, `options`)
```

## Description

`plot::Group2d` forms a group of any number of graphical 2D objects.

Grouping together a larger number of graphical objects and accessing the group as a whole simplifies their handling. In particular, the main purpose of a group is to inherit graphical attributes that are shared by all members of the group.

To change the inherited attributes interactively, do not select the group itself in the interactive object browser of the MuPAD® graphics tool (see Viewer, Browser, and Inspector: Interactive Manipulation). Underneath the group object, find 'defaults' branches for the objects in the group. Select the 'defaults' branch for the object type that you want to set attributes for.

A group can contain groups.

 Note:   When working with groups of points, the more efficient approach is to use the specialized grouping construct `plot::PointList2d` instead of generic groups of points.

## Attributes

AttributePurposeDefault Value
`Name`the name of a plot object (for browser and legend)
`Visible`visibility`TRUE`

## Examples

### Example 1

Consider a group `G1` consisting of two triangles inscribed in an ellipse. Form a new group `G2` consisting of the group `G1`, the ellipse and its focal points. The entire figure given by the group `G2` is rotated by an animated `plot::Rotate2d`:

```G1 := plot::Group2d( plot::Polygon2d([[0, -1], [0, 1], [-2, 0]]), plot::Polygon2d([[0, -1], [0, 1], [ 2, 0]]), Closed = TRUE, Filled = TRUE, Color = RGB::Blue): G2 := plot::Group2d( G1, plot::Ellipse2d(2, 1,[0, 0]), plot::PointList2d([[-sqrt(3), 0], [sqrt(3), 0]]), PointSize = 2*unit::mm, PointColor = RGB::Red, LineColor = RGB::Black): plot(plot::Rotate2d(a, [0, 0], a = 0..2*PI, G2))```

`delete G1, G2:`

## Parameters

 ```object2d1, object2d2, …``` Graphical 2D objects