Using the drawline function to get distance and intensities between endpoints

I am using this function https://www.mathworks.com/help/images/ref/drawline.html to draw a line across an image. My goal is to get the distance between the endpoints and get the intensity across the line.

disp('Please draw a line from the anterior edge of the patient to the center of the prostate');
    anteriorLine = drawline(fh.CurrentAxes,'Color','r');
    
    % Calculate the length of the line in physical units
    % anteriorLine.Position
    Distance = anteriorLine.Position;
    x1 = Distance(1,1); y1 = Distance(1,2); x2 = Distance(2,1); y2 = Distance(2,2);

    % Interpolate the intensities allong the line in increments of 0.1 mm
    
    % Plot intensities allong line

I am having trouble with the position code in the link I shared above and I don't even know where to start with interpolating the intensities across the line. I would greatly appreciate a starting point or some help, thank you.

[Walter Roberson]

See improfile()

[Kyle Williams]

I have been trying that but I don't know how to include improfile() in my code. I have to use it in the command window for it to work.

Answer 1

[Image Analyst]

Try this:

grayImage = imread('moon.tif');
subplot(2, 1, 1);
imshow(grayImage);
drawnow;
uiwait(helpdlg('Left click the first point and right click the second point.'))
[xLine, yLine, intensities] = improfile;
hold on;
plot(xLine, yLine, 'b-', 'LineWidth', 2)
subplot(2, 1, 2);
plot(intensities, 'b-', 'LineWidth', 2)
grid on;
xlabel('Distance')
ylabel('Gray Level')

[Kyle Williams]

This code works great. When I try it with mine, the line disppears after I draw the line and I don't get a plot. Idk why.

[Image Analyst]

You probably changes it, like you don't have the line

plot(xLine, yLine)

Attach your code if you still want help with it.