Uniformly distributed vectors

Create uniformly distributed vectors using the algorithm Spherical Fibonacci Spiral points on a sphere algorithm (John Burkardt) or Golden Section Spiral points on a sphere.

Usage

v_unif(class = NULL, n = 100, method = c("gss", "sfs", "rotasym"))

Arguments

class

character. Coordinate class of the output vectors.

n

number of observations

method

character. The algorithm for generating uniformly distributed vectors. Either "sfs" for the "Spherical Fibonacci Spiral points on a sphere", "gss" for "Golden Section Spiral points on a sphere", or the algorithm rotasym::r_unif_sphere() from the rotasym package.

Value

object of class specified by "class" argument

Details

"sfs" algorithm is from on John Burkardt (http://people.sc.fsu.edu/~jburkardt/), "gss is from http://www.softimageblog.com/archives/115

See also

rvmf() to draw samples from the von Mises Fisher distribution around a specified mean vector.

Examples

v_unif("line", n = 100, method = "sfs") |>
  ortensor() |>
  or_eigen()
#> eigen() decomposition
#> $values
#> [1] 0.1114462 0.1111266 0.1107611
#> 
#> $vectors
#>               x             y            z
#> [1,] -0.7218896 -3.330669e-16 6.920082e-01
#> [2,]  0.0000000  1.000000e+00 4.440892e-16
#> [3,]  0.6920082 -3.330669e-16 7.218896e-01
#> 
v_unif("line", n = 100, method = "gss") |>
  ortensor() |>
  or_eigen()
#> eigen() decomposition
#> $values
#> [1] 0.13900275 0.10703235 0.09000676
#> 
#> $vectors
#>               x          y           z
#> [1,]  0.1044082  0.3128949 -0.94403162
#> [2,]  0.9656739 -0.2589081  0.02098788
#> [3,] -0.2378504 -0.9138180 -0.32918657
#> 
v_unif("line", n = 100, method = "rotasym") |>
  ortensor() |>
  or_eigen()
#> eigen() decomposition
#> $values
#> [1] 0.17030469 0.11962501 0.05829888
#> 
#> $vectors
#>               x           y           z
#> [1,]  0.9557608 -0.24096646 -0.16869059
#> [2,] -0.2422017 -0.97013158  0.01352918
#> [3,] -0.1669121  0.02792649 -0.98557620
#>