Vector Visualization Vector VisualizationIf the Vectors item in the Display Options dialog is toggled for display, vector plots can be generated using the active vector data set for the object. Vectors are placed at specified nodes or cells, or displayed across the mesh or grid with uniform spacing based on user defined options. The display of vectors can be controlled using the Vector Options dialog which is accessed through the Vector Opts command in the Data menu or from the Data Browser or Display Options dialogs.
The upper left portion of the Vector Options dialog allows the user to specify the shape of the vector arrows by specifying proportional head length, head width, shaft length and shaft width.
In the lower left, the user specifies how big the arrows will appear in the graphics window. This can be a constant length, a scaled length, or a range of lengths. The min and max arrow sizes are displayed in the canvas just above this section of the dialog.
The upper right portion of the dialog is used to specify the arrow color. Arrows may be a constant color, or shaded according to magnitude. If a ramp of colors is desired, the color of the vector is extracted from a ramp. By default, the arrow with the smallest magnitude is displayed in the color at the bottom end of the ramp, and the arrow with the largest magnitude is displayed in the color at the top of the ramp. Intermediate magnitudes are interpolated to select an appropriate intermediate color. Alternately, the user can define the magnitudes that map to the top and bottom of the ramp. If this option is used, any arrow with a magnitude lower than the minimum is displayed in the color at the bottom of the ramp, and any arrow with a magnitude greater than the maximum is displayed with the color at the top of the ramp.
The lower right portion of the dialog allows the user to control the density of arrow to be displayed. In a very dense mesh, a large number of data points may be displayed very close together on the screen. Therefore, if a vector is displayed at every point, the picture can become a jumble of vectors on top of each other. One way to treat this is to zoom in on a specific portion of the mesh, so the nodes are not displayed so close together. However, if the desired region of the mesh is still too dense, or zooming in is not acceptable, the user can filter the displayed vectors. SMS provides four methods of filtering vectors. These include:
Vectors above and below extremes may be turned off.
Vectors at midside nodes may be turned off.
A random sampling of vectors may be used.
The default values button at the bottom fills in a set of values based on the values in the initial conditions file.
The lower right portion of the vector options also includes a toggle for a vector legend. The vector legend displays the significance of the size of the vectors displayed on the grid.