Ignore double click with ginput in MATLAB

My question is rather simple, does anyone know a way to have matlab's ginput ignore subsequent clicks at the same location?

I've thought of some possibilities, like a for loop that checks the stored arrays for identical values and remove them, but then I run into trouble with the length of the for loop (as the arrays change size by removing stuff), so that doesn't work. I suppose there should be some easy workaround, but I haven't been able to figure one out yet..

Simple code but little bit more user effort version

%%// Tolerance
TOL = 5;

%%// Start selecting points for an unlimited number, until Return key is pressed
[x y ] = ginput;
xy = [x y];
xy(sum(abs(diff([x y])),2)<TOL,:) = []; %%// Remove the "nearby points"

Naive and safer approach

%%// Tolerance
TOL = 5;

%%// Number of points to be clicked
N = 4;

%%// Clicked points array to be stored here
xy_all = zeros(N,2);

%%// First point
[x y ] = ginput(1);
cmp1 = [x y];
xy_all(1,:) = [x y];

%%// Second point onwards
k=2;
while k<=N
    [x y ] = ginput(1);
    if sum(sum(abs([x y]-cmp1)))>TOL
        cmp1 = [x y];
        xy_all(k,:) = [x y];
        k= k+1;
    end
end