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Extract data points from image in annular space with radius R1 and R2

I have a 3000 * 3000px image. I first find the center of my area of ​​interest, say at position (1000,2000). I want to extract data into ring space with R1 = 10 pixels, R2 = 20 pixels and find the data mode in ring space. Is there some python routine for this, or any smart and concise way to implement it? I know I photutils.aperture_photometry

can get the sum of the ring, but not the individual data points at each pixel.

import numpy as np
data = np.random.uniform(0,10,size=(3000,3000))
center = (1000,2000)    #### in pixel space
R1 = 10   #### pixels
R2 = 20   #### pixels
....
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No answer ... Surprised. I have a very simple two loop function to do this.

imin = center[0] - R2
imax = center[0] + R2 + 1
jmin = center[1] - R2
jmax = center[1] + R2 + 1
target = []
for i in np.arange(imin, imax):
    for j in np.arange(jmin, jmax):
        ij = np.array([i,j])
        dist = np.linalg.norm(ij - np.array(center))
        if dist > R1 and dist <= R2:
            target.append([i,j,data[i][j]])
target = np.array(target)


Any better implementation?

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