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getPosition

Return current position of ROI object

getPosition is not recommended. Using the new ROIs, retrieve the position of the ROI by accessing the value of Position property instead. For more information, see Compatibility Considerations.

Description

pos = getPosition(h) returns the current position of the ROI object, h.

Input Arguments

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ROI object, specified as an imellipse, imfreehand, imline, impoint, impoly, or imrect object.

Output Arguments

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Position of the ROI object, returned as a numeric array. The shape of the array depends on the type of ROI object.

ROI ObjectReturned position
imellipse4-element vector of the form [xmin ymin width height], representing the size and position of a bounding box around the ellipse. The initial size of the bounding box is width-by-height pixels. The upper-left corner of the box is at the (x,y) coordinate (xmin,ymin).
imfreehandn-by-2 matrix. The two columns define the x- and y-coordinates, respectively, of the n points along the boundary of the freehand region.
imline2-by-2 matrix of the form [x1 y1; x2 y2], representing the position of the two endpoints of the line.
impoint1-by-2 vector of the form [x y].
impolyn-by-2 matrix. The two columns define the x- and y-coordinates, respectively, of each of the n vertices.
imrect4-element vector of the form [xmin ymin width height]. The initial size of the rectangle is width-by-height pixels. The upper-left corner of the rectangle is at the (x,y) coordinate (xmin,ymin).

Version History

Introduced in R2008a

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R2018b: getPosition is not recommended

Starting in R2018b, a new set of ROI objects replaces the existing set of ROI objects. The new objects provide more functional capabilities, such as face color transparency. The new classes also support events that you can use to respond to changes in your ROI such as moving or being clicked. Although there are no plans to remove the old ROI objects at this time, switch to the new ROIs to take advantage of the additional capabilities and flexibility. For more information on creating ROIs using the new ROI functions, see Create ROI Shapes.

To retrieve the current position of the ROI, access the value of the Position property of the ROI.

Update Code

Update all instances of getPosition.

Discouraged UsageRecommended Replacement

This example creates an ROI and uses getPosition to retrieve the current location of the ROI.

imshow('cameraman.tif');
h = imrect(gca,[10 10 100 100]);
pos = getPosition(h)

Here is equivalent code, replacing the old ROI with a new ROI object and then accessing the value of the Position property of the ROI.

imshow('cameraman.tif');
h = drawrectangle(gca,'Position',[10 10 100 100]);
pos = h.Position