function [Y] = HillEQ(x,k,tau)
%Hill-Type function equation
%input X value, k (exp), and tau (IC50)
%output Y
%call: HillEQ(x,k,tau)
%x>0; stops errors in ODE solvers
%DC Kirouac 1-9-2016
Y = (max(0,x).^k)./(tau^k + max(0,x).^k);
end