what does allcentroids do?

allAreas = [measurements.Area];
allPerimeters = [measurements.Perimeter];
allCentroids = [measurements.Centroid];
centroidX = allCentroids(1:2:end);
centroidY = allCentroids(2:2:end);

[Walter Roberson]

That looks like code I might have written ;-)

Note that in the above, "allCentroids" is just another variable name, not the name of a command or function call. What will be stored in that variable is as the others have described below.

Answer 1

[Jeff E]

This is pulling the various measurements (Area, Perimeters, Centroid coordinates) out of the cell array measurements, and putting them into arrays. allCentroids will contain the centroid X and Y coordinates concatenated together along the lines of: ROI_1_Xcoord ROI_1_Ycoord ROI_2_Xcoord ROI_2_Ycoord ...

By taking every other element of allCentroids, centroidX contains the X coordinates, while centroidY contains the Y coordinates.

[noha maabreh]

what do you mean of this "ROI_1_Xcoord ROI_1_Ycoord ROI_2_Xcoord ROI_2_Ycoord"?

[Jeff E]

If your image has two ROIs with centroid XY coordinates as follows:

ROI1 - 50x 60y

ROI2 - 100x 120y

Then allCentroids would be an array containing: [50 60 100 120]

[noha maabreh]

thank you