Method: Bio::PDB::Utils.calculatePlane

Defined in:
lib/bio/db/pdb/utils.rb

.calculatePlane(coord1, coord2, coord3) ⇒ Object

calculates plane



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# File 'lib/bio/db/pdb/utils.rb', line 174

def calculatePlane(coord1, coord2, coord3)
  a = coord1.y * (coord2.z - coord3.z) +
      coord2.y * (coord3.z - coord1.z) + 
      coord3.y * (coord1.z - coord2.z)
  b = coord1.z * (coord2.x - coord3.x) +
      coord2.z * (coord3.x - coord1.x) + 
      coord3.z * (coord1.x - coord2.x)
  c = coord1.x * (coord2.y - coord3.y) +
      coord2.x * (coord3.y - coord1.y) + 
      coord3.x * (coord1.y - coord2.y)
  d = -1 *
      (
       (coord1.x * (coord2.y * coord3.z - coord3.y * coord2.z)) +
       (coord2.x * (coord3.y * coord1.z - coord1.y * coord3.z)) +
       (coord3.x * (coord1.y * coord2.z - coord2.y * coord1.z))
       )

  return [a,b,c,d]
end