1. Use MATLAB, to calculate locations of a circle with a radius of 10 and centering at (20,
20); assign the locations at the x-axis and the y-axis to an array of 2 by n, where n is the
number of 2-D points.
2. Use the plot function of MATLAB to plot the circle.
3. Draw a 2-D circle region with a radius of 100 in the center of an array of 400 by 400 by
given the elements inside the circle as 255 and 0 otherwise.
4. Apply a 7-step average smoothing process to the array and then display the array as a
black and white image.

下午急用,希望哪个高手帮回答下,最好写下解题方法,谢谢!!本人以后将长期光临,诸多问题还请赐教!!