Question

In a project that I am doing I need to reach floating indexed elements of a matrix. That is to say for instance I want to reach the (16.25,1) th element of a matrix. That might seem odd at the first glance. However, by (16.25,1), I mean the interpolation between (16,1) and (17,1) with weights of .25 and .75 respectively.

Is there a built-in function for that?

Many thanks,
Safak

Answer 1

You can use interp2:

Z = randi(10,10); % 10 x 10 random matrix with integers from 1 to 10
Z(1:2,1:2)
%ans =
%   2   4
%   7   6

% use interp2 to interpolate at row 1.5, col 2
z = interp2(Z,1.5,2)
% z = 6.5000