breast

f(x,y)=1/8*(6*exp((-((2/3*abs(x)-1)^2+(2/3*y)^2))-1/3*(2/3*y+1/2)^3)+2/3*exp((-(exp(1)^11))*((abs(2/3*x)-1)^2+(2/3*y)^2)^2)+2/3*y-(2/3*x)^4)