plot3d2

Arguments

X, Y, Z:

3 real matrices defining a data structure.

vect

a real vector.

<opt_args>

This represents a sequence of statements key1=value1, key2=value2,... where key1, key2,... can be one of the following: theta, alpha ,leg,flag,ebox (see definition below).

theta, alpha

real values giving in degree the spherical coordinates of the observation point.

leg

string defining the labels for each axis with @ as a field separator, for example "X@Y@Z".

flag

a real vector of size three. flag=[mode,type,box].

mode

an integer (surface color).

mode>0

the surface is painted with color "mode" ; the boundary of the facet is drawn with current line style and color.

mode=0:

a mesh of the surface is drawn.

mode<0:

the surface is painted with color "-mode" ; the boundary of the facet is not drawn.

Note that the surface color treatment can be done using color_mode and color_flag options through the surface entity properties (see surface_properties).

type

an integer (scaling).

type=0:

the plot is made using the current 3D scaling (set by a previous call to param3d, plot3d, contour or plot3d1).

type=1:

rescales automatically 3d boxes with extreme aspect ratios, the boundaries are specified by the value of the optional argument ebox.

type=2:

rescales automatically 3d boxes with extreme aspect ratios, the boundaries are computed using the given data.

type=3:

3d isometric with box bounds given by optional ebox, similarly to type=1.

type=4:

3d isometric bounds derived from the data, similarly to type=2.

type=5:

3d expanded isometric bounds with box bounds given by optional ebox, similarly to type=1.

type=6:

3d expanded isometric bounds derived from the data, similarly to type=2.

Note that axes boundaries can be customized through the axes entity properties (see axes_properties).

box

an integer (frame around the plot).

box=0:

nothing is drawn around the plot.

box=1:

unimplemented (like box=0).

box=2:

only the axes behind the surface are drawn.

box=3:

a box surrounding the surface is drawn and captions are added.

box=4:

a box surrounding the surface is drawn, captions and axes are added.

Note that axes aspect can also be customized through the axes entity properties (see axes_properties).

ebox

It specifies the boundaries of the plot as the vector [xmin,xmax,ymin,ymax,zmin,zmax]. This argument is used together with type in flag : if it is set to 1, 3 or 5 (see above to see the corresponding behaviour). If flag is missing, ebox is not taken into account.

Note that, when specified, the ebox argument acts on the data_bounds field that can also be reset through the axes entity properties (see axes_properties).

Description

plot3d2 plots a surface defined by rectangular facets. (X,Y,Z) are three matrices which describe a surface. The surface is composed of four sided polygons.

The X-coordinates of a facet are given by X(i,j), X(i+1,j), X(i+1,j+1) and X(i,j+1). Similarly Y and Z matrices contain Y and Z-coordinates.

The vect vector is used when multiple surfaces are coded in the same (X,Y,Z) matrices. vect(j) gives the line at which the coding of the jth surface begins. Like in plot3d, the same properties are editable (see surface_properties and axes_properties).

Examples

u = linspace(-%pi/2,%pi/2,40);
v = linspace(0,2*%pi,20);
X = cos(u)'*cos(v);
Y = cos(u)'*sin(v);
Z = sin(u)'*ones(v);
plot3d2(X,Y,Z);
e=gce();
e.color_mode=4; // change color
f_data=e.data;
TL = tlist(["3d" "x" "y" "z" "color"],f_data.x,f_data.y,f_data.z,10*(f_data.z)+1);
e.data=TL;
e.color_flag=2;

See also

• plot3d — 3D plot of a surface
• genfac3d — calcule les facettes d'une surface 3D non-paramétrique