Simulates responses using a Frequency of Seeing (FoS) curve.
For internal use only, use opiInitialize().
The FoS is modelled as a cumulative Gaussian function over dB with
standard deviation equal to min(cap, exp( A * t + B)), where
t is the threshold/mean of the FoS in dB.
All values are in dB relative to maxStim.
Value
A list with elements:
err NULL if initialised, msg otherwise
Arguments
type
A single character that is:
N for using the A and B values from the Normals in Henson et al (2000)
G for using the A and B values from the Glaucomas in Henson et al (2000)
C for using the A and B values from the Combined in Henson et al (2000)
X to specify your own A and B values as parameters
A
Coefficient of t in the formula (ignored if type != 'X').
B
Addend of t in the formula (ignored if type != 'X').
cap
Maximum dB value for the stdev of the FoS curve.
maxStim
The maximum stimulus value (0 dB) in cd/\(\mbox{m}^2\).
# Set up a simple simulation for white-on-white perimetrychooseOpi("SimHenson")
res <- opiInitialize(type = "C", cap = 6)
if (!is.null(res$err))
stop(paste("opiInitialize() failed:", res$err))