visualFields (version 0.6.2)

gcloc2psi: Angle of incidence in the optic nerve head for vf locations

Description

This is the inverse of the model: it obtains the angle of incidence psi of the average path that passes through position (x,y)

Usage

gcloc2psi( xy, r0 = 4 )

Arguments

xy

Visual field location in Cartesian coordinates

r0

Radius of the optic head nerve. It is a necessity of the model and changing it, changes the calculated average bundle paths. Default value is 4

Value

The angle of incidence psi of the average path that passes through position (x,y)

References

[1] N. M. Jansonius, J. Nevalainen, B. Selig, L. M. Zangwill, P. A. Sample, W. M. Budde, J. B. Jonas, W. A. Lagreze, P. J. Airaksinen, R. Vonthein, L. A. Levin, J. Paetzold, and U. Schiefer. A mathematical description of nerve fiber bundle trajectories and their variability in the human retina. Vision Research, 49(17):2157-2163, 2009.

[2] N. M. Jansonius, J. Nevalainen, B. Selig, L. M. Zangwill, P. A. Sample, W. M. Budde, J. B. Jonas, W. A. Lagreze, P. J. Airaksinen, R. Vonthein, L. A. Levin, J. Paetzold, and U. Schiefer. Erratum to "a mathematical description of nerve fiber bundle trajectories and their variability in the human retina" [vision research 49(17) (2009) 2157-2163]. Vision Research, 50:1501, 2010.

[3] N. M. Jansonius, J. Schiefer, J. Nevalainen, J. Paetzold, and U. Schiefer. A mathematical model for describing the retinal nerve fiber bundle trajectories in the human eye: Average course, variability, and influence of refraction, optic disc size and optic disc position. Experimental Eye Research, 105:70-78, 2012.

See Also

fiberpathpsi

Examples

# NOT RUN {
  gcloc2psi( data.frame( x = c( 0, 10 ), y = c( 0, 10 ) ) )
# }