WINDS_Treecode.f90

Paralleled Treecode algorithm for the acceleration of Biot-Savart Law in free vortex method. Modified for vortex filament method with Simpson's Rule.

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Primary author:

Hans Johnston (johnston@math.umass.edu). Department of Mathematics. University of Massachusetts, Amherst.

Refer to http://www.math.umass.edu/~johnston/newtreecode.html

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INPUTS:

•    fila_x: x coordinates of source vortex filaments 
  

•    fila_y: y coordinates of source vortex filaments
  

•    fila_z: z coordinates of source vortex filaments
  

•    points: Target/receiving particles
  

•    GAMMA_array: Strength of source vortex filaments
  

•    RC_array: Core radius of source vortex filaments
  

•    Parameters: parameters for Treecode Algorithm
  

•    OtherState: not used here
  

•    Discrete_states: not used here
  

OUTPUTS:

•    Uind_array: induced velocity for all the target/receiving particles
  

•    ErrStat, ErrMess: error information