Combine PolygonROI

Combine several PolygonROI.

import hyperspy.api as hs

Create a signal:

s = hs.data.atomic_resolution_image()

Create the ROIs, here PolygonROI:

roi = hs.roi.PolygonROI([(2, 4.5), (4.5, 4.5), (4.5, 2), (3.5, 3.5)])
roi2 = hs.roi.PolygonROI([(0.5, 0.5), (1.2, 0.2), (1.5, 1), (0.2, 1.4)])

We plot the signal add the ROIs to the figure using add_widget().

s.plot()
roi.add_widget(s, axes=s.axes_manager.signal_axes)
roi2.add_widget(s, axes=s.axes_manager.signal_axes)

<hyperspy.drawing._widgets.polygon.PolygonWidget object at 0x7fa82e912310>

Now that we have two ROIs, roi and roi2, we can combine them to slice a signal by using the following function:

s_roi_combined = hs.roi.combine_rois(s, [roi, roi2])
s_roi_combined.plot()

It is also possible to get a boolean mask from the ROIs, which can be useful for interacting with other libraries. You need to supply the signal’s axes_manager to get the correct parameters for creating the mask:

boolean_mask = hs.roi.mask_from_rois([roi, roi2], s.axes_manager)
boolean_mask = hs.signals.Signal2D(boolean_mask)
boolean_mask.plot()