fec properties description of the fec entities properties

## Description

The Fec entity is a leaf of the graphics entities hierarchy. It represents 2D finite elements plots (see `fec`, `Sgrayplot`).

parent:

  This property contains the handle of the parent. The parent of the fec entity should be of the type `"Axes"` or `"Compound"`.

children:

  This property contains a vector with the `children` of the handle. However, `Fec` handles currently do not have any `children`.

visible:

  This field contains the `visible` property value for the entity . It should be `"on"` or `"off"` . By default, the plot is visible, the value's property is `"on"`. If `"off"` the plot is not drawn on the screen.

data:

  This is a three column matrix `[x,y,f]`, where `x(i)` and `y(i)` are the coordinates of the `i`'th node. `f(i)` is the value associated to the node `i`.

triangles:

  This is a `[Ntr,N+2]` matrix. Each line of `triangles` specifies a convex polygon of the mesh `triangles(j) = [number,node1,node2,node3, ..., nodeN, flag]`. `node1,node2,node3, ..., nodeN` are the number of the nodes which constitutes the polygon. number is the number of the polygons and flag is an integer not used.

z_bounds:

  This vector of size 2, `[zmin,zmax]`, gives the z values associated with the first and the last color (of the current colormap). More exactly if the colormap have `nc` colors and if we note `dz = (zmax-zmin)/nc` ,then the part of the triangulation where `zmin + (i-1)dz <= z < zmin + i dz` is filled with the color `i`). By default the `z_bounds` property value is `[0,0]`. In this case, the `zmin` and `zmax` are autommatically set to the minimum and maximum of the `func` argument.

outside_color:

  This vector of size 2, `[cmin, cmax]`, defines the color used when nodes values are outside the `z_bounds = [zmin,zmax]` interval. When node values are lower than `zmin` the color with index `cmin` is used. When node values are greater than `zmax` the color with index `cmax` is used. By default, the `outside_color` property value is `[0,0]`. In this case, `cmin` and `cmax` are automatically set to the two bounds of the colormap. If `cmin` or `cmax` are negative, then values outside z_bounds interval are not displayed, they appear transparent.

color_range:

  This vector of size 2, `[rmin, rmax]`, allows to use only a part of the colormap for display. `rmin` and `rmax` stand for colormap indices. If they are both greater than 1, then the actual colormap used to display the fec entity is `colormap(rmin:rmax)` where `colormap` is the colormap of the parent figure. By default, the `color_range` property value is `[0,0]`. In this case, the whole colormap is used.

line_mode:

  If `"on"`, the wireframe enclosing triangles is drawn. If `"off"`, only the inside of triangles are drawn.

foreground:

  This color index specifies the color of the mesh. If `line_mode` property is `"on"`, the wireframe is drawn using this color.

clip_state:

  This field contains the `clip_state` property value for the fec. It should be :

  - `"off"` this means that the fec is not clipped.

  - `"clipgrf"` this means that the fec is clipped outside the Axes box.

  - `"on"` this means that the fec is clipped outside the rectangle given by property clip_box.

clip_box:

  This field is to determinate the `clip_box` property. By Default its value should be an empty matrix if clip_state is "off". Other cases the vector `[x,y,w,h]` (upper-left point width height) defines the portions of the fec to display, however `clip_state` property value will be changed.

user_data:

  This field can be use to store any scilab variable in the fec data structure, and to retrieve it.

## Examples

    x=-10:10; y=-10:10;m =rand(21,21);
    Sgrayplot(x,y,m);
    a=get("current_axes");
    f=a.children.children(1)
    f.data(:,3)=(1:size(f.data,1))';
    a.parent.color_map=hotcolormap(64);

## See also

- set
- get
- delete
- fec
- Sgrayplot
- graphics_entities