Lock options

TheLock menu and toolbar, both shown in Figure 6-20, allow you to lock certain visualization window attributes so that when you change them, other locked visualization windows also update. Currently, you can lock the view and you can lock time.

5.11.1 Locking views

If you have created plots from related databases in multiple visualization windows, you can lock the views for the visualization windows together so as you change the view in one of the visualization windows with a locked view, the other visualization windows with locked views also update to have the same view. There are three types of views in VisIt: curve, 2D, and 3D. If you have 2D plots in a visualization window, the visualization window is considered to be 2D. Locking that 2D visualization window’s view will only update other visualization windows that are also 2D and vice-versa. The same is true for curve and 3D views. To lock a visualization window’s view, select theLock->View

option from theMain Window’s Windowmenu or use the visualization menu’sPopup menu orToolbar.

5.11.2 Locking time

If you have created plots from related databases in multiple visualization windows, you can lock the visualization windows together in time so as you change time in one visualization window, it updates in all other visualization windows that are locked in time.To lock a visualization window in time, select theLock->Time option from the

Main Window’s Window menu.

Figure 6-20: Lock menu and toolbar

Lock menu

Lock view Lock time

Overview VisIt User’s Manual 163

1.0

Overview

Many scientific databases can be decomposed into subsets that represent only part of the database. It is common to decompose databases into subsets based on Materials (regions), Domains, Groups, AMR patches, AMR levels, Species, Assemblies, etc. Databases are decomposed for a variety of reasons including breaking the database into smaller sized pieces that can be calculated in parallel using a computer with multiple processors. When VisIt is used to visualize the results of a simulation that has been divided into smaller subsets, it is often useful to restrict the size of the database, to increase performance, by using VisIt’sSubset Window.

2.0

What is a subset?

A subset is a set each of whose elements is an element of an inclusive subset. In other words, a subset is a smaller part of something. In simulation terms, a subset might be the cells containing a particular material in a mesh. A subset might be the part of the

simulation mesh that ran on computer processor 10. A subset might be the part of a simulated vehicle that is a tire. In many input database formats, this subset information is encoded in the file or can be inferred from how the file is structured. This leads to an organization of the data where many possible subsets may exist. If there is more than one way to create a subset, you can start asking questions like where in the mesh is there aluminum on only the parts that were computed on processor 2.

164 Subset Inclusion Lattice

3.0

Subset Inclusion Lattice

VisIt relates all possible subsets in a database using what is called a Subset Inclusion Lattice (SIL). Ultimately the subsets in a database are cells that can be grouped into different categories such as material region, domain, patch, refinement level, etc. Each category has some number of possible values when taken together form a collection. A collection lets you group the subsets that have different values but are still part of the same category. For example, the mesh shown in Figure 7-1 is broken down into domain and material categories and there are 3 domain subsets in the domain category. VisIt uses the SIL to remove pieces of a database from a plotted visualization by turning off bottom level subsets that are arrived at through turning off members in various collections or turning off entire collections. When various subsets have been turned off in a SIL, the collective on/off state for each subset is known as a SIL restriction.

4.0

Using the Subset Window

You can open theSubset Window, shown in Figure 7-2, by clicking on theSubset

option in theMain Window’s Controlsmenu or by clicking on theSubseticon next to

D₁ D₂ D₃ M₁ M₂ Domains Materials 2 Materials 3 Domains Whole mesh D₁M₁ D₁M₂ D₂M₁ D₂M₂ D₃M₁ D₃M₂ Categories Collection

Using the Subset Window 165 the name of a plot in thePlot lists’s plot entries. VisIt’sSubset Window displays subset relations and provides controls that allow you to alter a plot’s SIL restriction by turning off parts of the database.

TheSubset Window initially has three panels that display the sets contained in a database though the window can display an unlimited number of panels as subsets are browsed. Each successive panel serves to further subset the database. The leftmost panel contains the top level set for the database being examined. The top level set, which includes all elements in the database, can usually be decomposed in various ways. For example, it can be decomposed by material, processor domain, etc. The various ways in which a database can be decomposed are called subset categories. The subset categories will vary according to the file format in which the database was written as well as the organization and naming conventions used in the database.