pchip This function returns piecewise cubic hermite interpolating polynomial. d=pchip(x,y) d= pchip(x,y,xx) x: points at which the function is defined y: function of variable xNote that the lengths of x and y should be the same. xx: points of interpolation d: vector of interpolantant at xx x=[0 1 2 3 4 5] y=[1 0 1 0 1 0] xx=linspace(0,5,800) v=pchip(x, y) v=pchip(x,y,xx) plot(x,y,xx,v,'o')