Query

VisIt uses queries to gather quantitative information from the database being visualized.

Connected Components

Add a pseudocolor plot, then add an isovolume operator, set min-max value for the isovolume operator, then go to menu, Controls->Query, find “Connected Components Summery”, click “Query” button. The result will be saved into a .okc file, and can be opened in VisIt and plot as histogram. http://visitusers.org/index.php?title=Connected_components

_images/isovolume_attribute.png _images/pseudocolor_isovolume.png _images/cc_query.png

Python code:

OpenDatabase("databasename")
AddPlot("Pseudocolor", "varname")
DrawPlots()
Query("NumNodes")
print "The float value is: %g" % GetQueryOutputValue()

Query over time

check the “Do Time Query” box to enable query over time (very time consuming):

_images/volume_query_overtime.png

Python code:

for state in range(TimeSliderGetNStates()):
  print state
  SetTimeSliderState(state)
  DrawPlots()

  Query("MinMax")