function MTF = MTFip(q, p, age, m)
% MTF = MTFip(q, p, age, m) Calculates the modulation transfer function (MTF)
%	based on data from Ijspeert et al. 1992. All input variables are optional
%	except for q
%
%Input variables:
%	q = frequency in c/deg		
%	p = pupil diameter in mm		Default = 4 mm
%   age = age in years				Default = 0 years
%	m = pigmentation parameter		Default = call to pigment function
%

function LSF = LSFip(phi, age, p, m)
%LSFip(phi, age, p, m)	Calculates the linespread function (LSF) based on the 
%	equations espoused by Ijspeert et al. The user must specify the angle,
%	phi, in degrees. All other values are optional, and will be set at the 
%	following defaults if not specified:
%
%	age = age of subject in years 	Default age = 0 years	
%	p = pupil diameter in mm 		Default value = 4 mm.
%	m = pigmentation parameter		Default = call to pigment function
%

%PSFip(phi, age, p, m)	Calculates the pointspread function (PSF) based on the 
%	equations espoused by Ijspeert et al. The user must specify the angle,
%	phi, in degrees. All other values are optional, and will be set at the 
%	following defaults if not specified:
%
%	age = age of subject in years 	Default age = 0 years	
%	p = pupil diameter in mm 		Default value = 4 mm.
%	m = pigmentation parameter		Default = call to pigment function