ImageJ2 script to perform an operation over the rows of a dataset

iterateRows.groovy

#@ Dataset img

/**
 * Perform an operation on every row of the input image.
 * 
 * This sets every pixel in the first row to have value zero,
 * the second row will have value one, etc.
 * 
 * https://forum.image.sc/t/best-way-to-iterate-over-columns-rows/82472
 */

// number of rows = length in the y-dimension
nrows = img.dimension(1);

// value starts at zero
value = Util.getTypeFromInterval(img);
for( long r = 0; r < nrows; r++ ) {
	
	// get the rth row of the image
	rowImage = Views.hyperSlice( img, 1, r )
	
	// set every pixel in the row to value
	rowImage.forEach( x -> {
			x.set(value);
	});
	
	// increment value (value = value + 1)
	value.inc();
}
 
import net.imglib2.view.Views;
import net.imglib2.util.Util;