Error: The expression to the left of the equals sign is not a valid target for an assignment.

For some unknown reason I am getting this error on every line past line 14 (deleting the line causes the error to jump to the next line). Any help would be very much appreciated.

clear, clc
%Read image
img=im2double(imread('axial_CT_slice.bmp'));
[X, Y]=size(img);

%Set two seeds
s1x=130; s1y=150; %Note that seed location is not central to object
s2x=200; s2y=200;
seeds = [sub2ind([X Y],s1y,s1x),sub2ind([X Y]);
%Apply the random walker algorithms

%Build graph
%Generate points
rangex = 0:(X-1); %<- where the error is now
rangey = 0:(Y-1);
[x, y]=meshgrid(rangey,rangex);
points=[x(:),y(:)]; %cont.

Answer 1

[Jon]

I can't figure out why you're getting an error, but it works if you put square brackets around the expression, like this

rangex = [0:(X-1)];

EDIT: that actually doesn't work. You're not closing your seeds = [stuffhere bracket. Ie, it should read

seeds = [sub2ind([X Y],s1y,s1x),sub2ind([X Y])];

Answer 2

[Walter Roberson]

Why are you calling sub2ind([X Y]) without the expected multiple arguments?