I am getting an error Undefined function or variable ***. The first assignment to a local variable determines its class.

I am getting an error when converting the matlab code to HDL using HDL coder during workflow, "Undefined function or variable 'idx'. The first assignment to a local variable determines its class." and also this error "X must be 'double', 'single', 'logical', or 'char'."

Here is the code

      clc
close all;
im=imread('01_h.jpg');
im=imresize(im, [512 512]);
[result, c]=func(im);
imshow(result);

this calls the function

function [color1, centroid] = func(im)
[idx cent]=kmeans(im(:),2,'distance','sqEuclidean','Replicates',3);
color1 = zeros(size(im));
color1(idx==1) = im(idx==1);
end

what should i do to fix it?

[KSSV]

There is a little correction in func

function [color1, centroid] = func(im)
[idx,centroid]=kmeans(im(:),2,'distance','sqEuclidean','Replicates',3);
color1 = zeros(size(im));
color1(idx==1) = im(idx==1);
end