Cant get makima to work

I'm trying to inteprolate my data, with these three functions.

"spline" and "pchip" are borh working.

But the makima function doea not work.

xq1 = 0 :0.5: 20;
s_0k4 = spline(0k4(2,:),0k4(1,:),xq1);
p_0k4 = pchip(0k4(2,:),0k4(1,:),xq1);
m_0k4 = makima(0k4(2,:),0k4(1,:),xq1);
Error: "Undefined function or variable 'makima'."

I'm working with Matlab R2018b

Answer 1

[Stephan]

makima was introduced in R2019b - with R2018b it can not work. If possible update your matlab release.