mregion

 

Define a material region from a set of surfaces by logically combining the surface names and region names. The operators lt, le, gt, and ge are applied to previously defined surfaces according to the following rules.

Format

mregion / region_name / relation_oper surf_name [logic_oper relation_oper surf_name] [...]

 

mregion Parameters

Parameters

Type/Value

Description/Default

region_name

char*32

Name of new region being defined by combing surfaces.

relation_oper

 

The region is defined by logically combining the surface names with the surface commands. The parentheses operators, ( and ), are used for nesting. Spaces are required as delimiters to separate all operators and operands; parentheses are operators and must be surrounded by spaces. Internal interfaces should be excluded when defining material regions. (i.e. use lt and gt ). External boundaries should be included when defining material regions. If a material regions consists of more than one region and the regions touch (i.e. share a region interface), then the region interface is not a material interface -- all the points on the region interface are interior to the material region. In this case use le or ge to include these region interface points in the material region as interior points.

 

lt

If the surface following is a volume then lt means inside not including the surface of the volume. If the surface is a plane or a sheet lt means the space on the side of the plane or sheet opposite to the normal not including the plane or sheet itself.

 

le

If the surface following is a volume then le means inside including the surface of the volume. If the surface is a plane or a sheet le means the space on the side of the plane or sheet opposite to the normal including the plane or sheet itself.

 

gt

If the surface following is a volume then gt means outside not including the surface of the volume. If the surface is a plane or a sheet gt means the space on the same side of the plane or sheet as the normal not including the plane or sheet itself.

 

ge

If the surface following is a volume then ge means outside including the surface of the volume. If the surface is a plane or a sheet ge means the space on the same side of the plane or sheet as the normal including the plane or sheet itself.

surf_name

char*32

Name of the surface combining.

logic_oper

 

Logical operators used to combine the relation_oper.

 

or

Union of surfaces.

 

and

Intersection of surfaces.

 

not

Complement of surface.
Rules

Interior interfaces must be included in one and only one region.

No two regions may overlap and there must be no voids.

The operators lt, le, gt, and ge can modify a previously defined surface, resulting in a regions.

The operators or, and, and not are applied to regions and mean union, intersection, and complement respectively.

The union of all regions must describe a connected object.

Parentheses are used for nesting. Parentheses are operators.

Spaces are required as delimiters to separate operators and operands.

Examples

mregion / mat1 / le box1 and ( lt sphere1 and ( lt plane1 or gt plane2 ) )

mregion / mat2 / regiona or regionb