shrewd.m

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Computes SHREWD weights for a given two- or three-angle spherical grid. See the paper by Eden and Levitt for details on now the algorithm works: http://dx.doi.org/10.1006/jmre.1998.1427

Syntax

    weights=shrewd(alphas,betas,gammas,max_rank,max_error)

Parameters

     alphas - alpha Euler angles (ZYZ active) of the 
              grid, in radians, set to all-zeros for
              two-angle grids

      betas - beta Euler angles (ZYZ active) of the 
              grid, in radians

     gammas - gamma Euler angles (ZYZ active) of the
              grid, in radians

   max_rank - maximum spherical rank to take into consi-
              deration when minimizing residuals

  max_error - maximum residual absolute error per spheri-
              cal function

Outputs

    weights - a vector of grid weights for each 
              [alpha beta gamma] point supplied.

See also

Integration grids, Appendix I: powder grids

Version 2.6, authors: Ilya Kuprov