Simulator Documentation

To use this simulator, you will need two things:

MATLAB installed on your computer.

The script files containing the simulator itself. (I will include a link so that you can download the necessary files).

This page takes you through the nuts and bolts of the simulation. It also assumes some basic familarity with MATLAB. If you desire a more detailed description of the biology behind the simulator, you should look at the description of stages of the ideal observer.

Starting the simulator

To start the simulator, first make sure that the simulator script files are in your MATLAB search path. Start MATLAB and then type:
>> sim_main where the '>>' is the MATLAB prompt.

Entering parameters

Once you start up the simulator, typing "1" for help will start up Netscape and bring you directly to this page. Next, you should immediately be prompted to input a series of parameters for the simulation.

This determines the background luminance for the stimuli. Sine wave gratings are modulated around this mean intensity. This input intensity is later translated into the mean number of photons absorbed for each cone.
This sets the number of wavelengths to be used in the stimuli. Each wavelength is assigned an equal fraction of the background intensity value so that the total mean intensity will be correct. Wavelengths between 380 and 730 nm at 5 nm increments are acceptable. Each wavelength also has an associated phase shift to allow the counterphase sine wave gratings (for isoluminant gratings). A phase shift of 0 means that the dampened sine wave grating is centered over the cone array.

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