3.6. Scatter Plot

The window Scatter plot displays pixel values for two raster bands as points in the 2D space. Scatter plots are useful for assessing ROI separability between two bands.

_images/scatter_plot.png — Scatter Plot

The functions are described in detail in the following paragraphs.

3.6.1. Scatter list

The Scatter list is a table that includes the spectral signatures added from the SCP dock.

S	MC ID	MC Name	C ID	C Name	Color
checkbox field; if checked, the spectral signature is displayed in the plot	signature Macroclass ID	signature Macroclass Name	signature Class ID	signature Class Name	signature color

The following tools are available.

Tool symbol and name	Description
Band X	X band of the plot
Band Y	Y band of the plot
	remove highlighted signatures from this list
	add highlighted spectral signatures to ROI & Signature list
Precision	use custom precision for calculation (precision should be selected according significant digits): * 4 = \(10^{-4}\) * 3 = \(10^{-3}\) * 2 = \(10^{-2}\) * 1 = \(10^{-1}\) * 0 = 1 * -1 = 10 * -2 = \(10^{2}\) * -3 = \(10^{3}\)
Calculate :	calculate the scatter plot for the ROIs checked in the list
	remove highlighted signatures from this list
	add a temporary scatter plot to the list (as `MC Name = tempScatter`) and start the plot calculation of the last temporary ROI (see Working toolbar)

Warning

Using a precision value that is too high can result in slow calculation or failure.

3.6.1.1. Plot

Left click and hold inside the plot to move the view of the plot. Use the mouse wheel to zoom in and out the view of the plot. Right click and hold inside the plot to zoom in a specific area of the plot.

Tool symbol and name	Description
Colormap	select a colormap that is applied to highlighted scatter plots in the list when is clicked; if no scatter plot is highlighted then the colormap is applied to all the scatter plots
	automatically fit the plot to data
	save the plot image to file (available formats are `.jpg`, `.png`, and `.pdf`)
x y	display x y coordinates of mouse cursor inside the plot

_images/example_scatter_plot.png — Example Scatter Plot