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[edit] 'key_aggregate' expression

Given a cell "key" variable and a cell variable (float array) to aggregate this expression sums values per key and assigns the aggregate value of each key onto where it occurs on the mesh.

[edit] Syntax

key_aggregate(key_var,value_var)

[edit] Example

Component Labels	Component Area

This example allows you to visualize the total area of each individual connected component in a mesh.

• Open rect2.silo
• Define a new expression: random_value

rand(quadmesh2d)

• Define a new expression: cc_area

key_aggregate(conn_components(quadmesh2d),area(quadmesh2d)) 

• Create a Pseudocolor plot of 'cc_area'
• Add an Isovolume operator change the default var to 'random_value' and set the max value = 0.3
• Add a DeferExpression operator and defer the 'cc_area' expression.
• Click Draw to view the plot.

For more information about VisIt connected components capabilities see Connected_components