Orientation-averaged spectrum
    
    spectrum_oa(cluster, material, medium = 1.33, quadrature = c("gl", "qmc",
  "random", "cheap"), Nq = 100, iterative = FALSE, precision = 0.001,
  Qmax = 10000, dN = Nq, method = c("solve", "cg", "oos"), Nsca = 50,
  maxiter = 30, tol = 1e-04, progress = FALSE, verbose = TRUE)
    
     Arguments
    
      - cluster
 
      - cluster (list)
 
      - material
 
      - material
 
      - medium
 
      - refractive index medium
 
      - quadrature
 
      - quadrature method, using either Gauss Legendre quadrature (default), Quasi Monte Carlo, random, or "cheap" (3 Axes)
 
      - Nq
 
      - number of integration points
 
      - iterative
 
      - logical, increase N until convergence (QMC only)
 
      - precision
 
      - relative diff between two runs (QMC only)
 
      - Qmax
 
      - maximum N if convergence not attained (QMC only)
 
      - dN
 
      - iterative increase in N (QMC only)
 
      - method
 
      - linear system (solve), conjugate-gradient (cg), or order-of-scattering (oos)
 
      - Nsca
 
      - quadrature points for scattering cross-section
 
      - maxiter
 
      - integer termination of iterative solver
 
      - tol
 
      - double, tolerance of iterative solver
 
      - progress
 
      - print progress lines
 
      - verbose
 
      - display messages
 
    
    
    Details
    OA spectrum
    
    References
    Y. Okada, Efficient numerical orientation quadrature of light scattering properties
with a quasi-Monte-Carlo method, Journal of Quantitative Spectroscopy and Radiative Transfer, Volume 109, Issue 9, June 2008, Pages 1719-1742.