function img=coolviz6(func)
%coolviz6('func')
%visualization of complex function (domain coloring)
%hue is the angle of complex function
%val is the black lines.It is the real and imaginary value
% of complex function
%sat is the white lines in between the color lines
%usage
%
% coolviz6
% calling coolviz6 without any argument draw z.^z
%
% coolviz6('sin(z)')
% plots sin(z) from -pi to pi in x-axis and -pi to pi in y-axis
%
% coolviz6('func')
% 'func' can be any function
% example: coolviz6('log(z)') , coolviz6( 'cot(z)')
% coolviz6('z.^2 - 1./z') , coolviz6('z.^3-cos(z)')........
% always use ./ .* .^ operators when passing 'func'
% any function is drawn from -pi to pi on x-axis and -pi to pi on y-axis
%
% to save image call function as
% img=coolviz6('log(z)');
% imwrite(img,'domaincolor.png','png');
%
if nargin==0
func='z.^z';
end
X = linspace(-pi,pi,500);
Y = linspace(-pi,pi,500);
lenx = length(X);
leny = length(Y);
Z = zeros(length(X),length(Y));
colors= zeros(length(X),length(Y),3);
ColorMset = zeros(lenx,leny,3);
colors_uint8 = zeros(lenx,leny,3,'uint8');
for n = 1:lenx
Z(n,:)= Y(:)+i*X(n);
end
Z=feval(inline(func),Z);
abs_z= abs(Z);
hue = angle(Z)/(2*pi);
hue = -min(min(hue))+hue;
%loop to limit absolute value of function from 0 to 2pi
for m=1:lenx*leny
if abs_z(m)>2*pi
abs_z(m)=2*pi;
end
end
sat = mod(abs(sin(2*abs_z)).^15,1);
%power is 15 to make white line wider
sat = 1 -(1-sat).^9;
sat = 0.1 + sat *0.9;
z_real=real(Z);
z_imag=imag(Z);
%loop to limit imaginary and real value of function from -pi to pi
for m=1:lenx*leny
if z_real(m)>pi || z_imag(m)>pi
z_real(m)=pi;z_imag(m)=pi;
elseif z_real(m)<-pi || z_imag(m)<-pi
z_real(m)=-pi;z_imag(m)=-pi;
else
z_real(m)=z_real(m);z_imag(m)=z_imag(m);
end
end
val = mod(abs(sin(pi*z_imag).*sin(pi*z_real).*...
cos(pi*z_imag).*cos(pi*z_real)).^0.5,1);
val = 1 -(1-val).^7;
val = 0.3 + val *0.7;
ColorMset(:,:,1) = hue;
ColorMset(:,:,2) = sat;
ColorMset(:,:,3) = val;
h_wait=waitbar(0,'Please wait...');
for mm=1:lenx
for nn=1:leny
a=ColorMset(mm,nn,1);
s=ColorMset(mm,nn,2);
v=ColorMset(mm,nn,3);
zo = floor(6*a);
rough = (zo);
f = a*6 - zo;
p = v*(1-s);
q = v*(1-s*f);
t = v*(1-s*(1-f));
switch (rough)
case 0
r=v; g=t; b=p;
case 1
r=q; g=v; b=p;
case 2
r=p; g=v; b=t;
case 3
r=p; g=q; b=v;
case 4
r=t; g=p; b=v;
case 5
r=v; g=p; b=q;
end
co = (256*r);
if(co>255)
co = 255;
end
colors(mm,nn,1) = co;
co = (256*g);
if(co>255)
co = 255;
end
colors(mm,nn,2) = co;
co = (256*b);
if(co>255)
co = 255;
end
colors(mm,nn,3) = co;
end
waitbar(mm/lenx,h_wait);
end
close(h_wait);
colors_uint8=uint8(colors);
image(X,Y,uint8(colors));
axis square
if nargout==1
img=colors_uint8;
end
%function end