The sort command creates a sort key for chosen node or element attributes. Sort can be in ascending or descending order and will not alter current mesh object values.

The mesh object is not re-ordered but a sort key is created. Use REORDER to change the node or element ordering of the mesh object.


sort/mo_name/bins /[ ascending or descending]/key_name/ sort_attribute / [epsilon_user]

sort/mo_name/index or rank/[ascending or descending]/key_name/ in_att1, in_att2, in_att3 ...

sort/mo_name/line_graph /[ascending or  descending]/key_name/[elements or nodes]

For all commands:

mo_name is the name of a valid mesh object or -def- which selects the currently active mesh object.

sort_type sorting methods include bins, index, rank and line_graph See below.

ascending or descending detirmines the ordering direction. Note this parameter is ignored by the line_graph method but must be present for consistency with other sort variations.

key_name is the name of the sort key attribute created. The reorder command uses this to reorder the mesh. This is an integer vector (VINT) which will hold the output sort key values. If no name is given for key_name, a name will be created which will be ikey_ and the first attribute name in sort_attributes. For the line_graph option, the default key_name will be called ikey_line_graph.

sort_attributes The name of one or more existing attribute names. Each attribute will be used as a node of element based array upon which the sorting routine will sort. Multi-key sorts can have an arbitrary number of input attributes. Attribute in_att1(n) has priority over in_att2(n) in breaking ties. Note: all attributes are put into a type real work array before being sent to the sort routine. Note the line_graph does not use attributes as it sorts line elements based on connectivity (see method below).

Single-Key sort:

bins is a single-key sort which assigns each in_att1 value a bin number. If in_att1 is an integer then bins each have a unique integer value associated with them. If in_att1 is a real number, bins are created with values which are within +-epsilon of each other, where epsilon=1.e-10 x abs(real_bin_value). If all array values are unique, then the maximum value of the index array will equal the number of entries in the sorted list. Otherwise, the maximum value of the index array will be less than the number of entries in the sorted list but will equal the number of unique entries in the list. With the bins method, an optional user specified epsilon multiplier, epsilon_user, will override the default value of 1.e-10.

Multi-Key sort:

index is a single or multi-key sort that constructs an index table such that in_att1(ikey(1)) is the first entry in the sorted array, in_att1(ikey(2)) is the second, etc.

rank is a single or multi-key sort that constructs a rank table such that the tables ith entry give the rank of the ith entry of the sorted arrays. The rank table is derived from the index table by:

 foreach j = 1,N
   rank(index(j)) = j

Line Graph sort:

line_graph is a sort for connected line segments for arranging into a reasonable order. The sorted order for components which are not polylines or polygons is unspecified, but it will usually be reasonable because the underlying algorithm visits the edges via depth first search. In particular, it makes the following guarantees:

  • Each connected component will be arranged together.
  • Polylines (chains of line segments with no branching or loops) will be in order from one end to the other.
  • Polygons will be in order starting from one segment and looping back around to the same place.

line_graph with elements generates the following three integer element attributes:

  • cid: A component id for distinguishing separate connected components. Each connected component receives a unique positive integer starting from one. This allows you to identify all the edges in a particular component by selecting all elements with a particular component id.
  • ctype: The component type, represented as an integer from 1 to 5.

    1 (Polyline)
    A connected chain of segments with no branches or loops.
    2 (Tree)
    A connected acyclic component.
    3 (Polygon)
    A component consisting solely of a single loop.
    4 (Shared Edges)
    A component which has a pair of cycles with a shared edge.
    5 (Other)
    Anything which does not fit into the above categories.
  • loop_id: This is a unique positive integer assigned to each simple cycle. Edges that are not part of a cycle receive a default value of zero. If an edge is shared (i.e. part of more than one cycle) then it will be labeled with only one of its cycles. In this case, the cycle corresponding to the label is not fully specified because there is more than one right answer.

line_graph with nodes is based on the option for elements, except that it does not create extra attributes. Based on the sorted elements, the nodes will be reordered in the same sequence. This is necessary for triangulation as “TRIANGULATE” routine requires the nodes to be in either clockwise or counterclockwise order.


     sort / cmo / line_graph / ascending / ikey / elements

Sort the line segment elements into a reasonable order based on connectivity. This also creates attributes cid, ctype, and loop_id (see above).

 sort / cmo / index / ascending / ikey / imt zic yic xic

Multi-key sort first by imt then to break ties consider z coordinate, then if there are further ties, use y coordinate. Use x coordinate as final tie breaker.

     sort / cmo / rank / descending / ikey / yic

Produce ranking of nodes based on y coordinate in descending order.

     sort / cmo / index /-def-/-def-/ xic yic zic

Produce index of noded coordinates. This would be like a line sweep sort where the sweep is first along x coordinate then y then z.

     sort / cmo / bins / ascending / i_index / xic
     sort/ cmo / bins / ascending / j_index / yic
     sort / cmo / bins / ascending / k_index / zic

If the cmo were a finite difference grid of points, the above three commands would produce the finite difference indexing. All points with the same x value would be in the same i_index bin, all points with the same y value would be in the same j_index bin, etc.

define MOGOOD motet
define MOSORT mopts

cmo/addatt/MOSORT id_mesh1 /VINT/scalar/nnodes/linear/permanent//0      
interpolate/voronoi/ MOSORT id_mesh1/1,0,0/ MOGOOD id_node

cmo/addatt/MOSORT id_diff /VINT/scalar/nnodes/linear/permanent//0      
math/sub/MOSORT id_diff/1,0,0/ MOSORT id_mesh1 /MOGOOD id_node
cmo/printatt/MOSORT/ id_diff / minmax

sort/ MOSORT/ index / ascending / ikey / id_mesh1
reorder/MOSORT/ ikey

Sort and reorder a set of nodes based on a source mesh, based on node id and position xyz. Use interpolate/voronoi to associate each node with the good mesh node id’s. We check to see if the ordering for both mesh objects is different by subtracting the node id of one from the second. The result would be 0 for all nodes that match position and node id. Sort mesh object using the attribute with the interpolated node id’s, then reorder using the ikey values.

LaGriT command file example 1 for sort and reorder

LaGrit command file example 2 for sort and reorder

OLD FORMAT - No longer supported but syntax will still work.

sort / xyz / [ index  bins  rank ]

sort/xyz/index sorts the x,y,z coordinate integer arrays i_index, j_index, k_index such that xic(i_index(i)) i=1,..nnodes lists the coordinate in ascending order.

sort/xyz/bins sorts the x,y,z coordinates and assigns each i_index, j_index, k_index values in ascending order of the bin number of the sorted list.

sort/xyz/rank sorts the x,y,z coordinates and assigns each i_index, j_index, k_index values the ranking of the node in the sorted list.

If all array values are unique, then the maximum value of the index array will equal the number of entries in the sorted list. Otherwise, the maximum value of the index array will be less than the number of entries in the sorted list but will equal the number of unique entries in the list.

 For example given x = 0, 1, 2, 1, 0

 sort/xyz/index returns i_index = 5, 1, 4, 2, 3

 sort/xyz/bins returns i_index = 1, 2, 3, 2, 1

 sort/xyz/rank returns i_index = 2, 4, 5, 3, 1