find_centre_of_density

clustertools.analysis.functions.find_centre_of_density(cluster, xstart=0.0, ystart=0.0, zstart=0.0, vxstart=0.0, vystart=0.0, vzstart=0.0, indx=None, nsphere=100, rmin=0.1, rmax=None, nmax=100, method='harfst', nneighbour=6)

Find cluster’s centre of density

• Find cluster’s centre of density:

  if method==’harfst’ use (Harfst, S., Gualandris, A., Merritt, D., et al. 2007, NewA, 12, 357) courtesy of Yohai Meiron if method==’casertano’ use (Casertano, S., Hut, P. 1985, ApJ, 298, 80)

Parameters:

clusterclass

StarCluster

xstart,ystart,zstartfloat

starting position for centre (default: 0,0,0)

vxstart,vystart,vzstartfloat

starting velocity for centre (default: 0,0,0)

indx: bool

subset of stars to perform centre of density calculation on (default: None)

nsphereint

number of stars in centre sphere (default:100)

rminfloat

minimum radius of sphere around which to estimate density centre (default: 0.1 cluster.units)

rmaxfloat

maxmimum radius of sphere around which to estimate density centre (default: None cluster.units, uses maximum r)

nmaxfloat

maximum number of iterations (default:100)

methodstr

method for finding the centre of density (‘harfst’ (default), ‘casertano’)

if method==’casertano’

nneighbourint

number of neighbours for calculation local densities

Returns:

xc,yc,zc,vxc,vyc,vzcfloat

coordinates of centre of mass