How to build a rotationally symmetric mask?

Hi everyone, suppose I have 'p' given by a generalized Gaussian function and want to make a rotationally symmetric mask of it (i.e. a 2d square). Any easy way?

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x = -6:0.01:6;

alfa=2; beta=10; mean=0;

p=(beta/(2*alfa*gamma(1/beta))).*exp(-((abs(x-mean)/alfa).^beta));

plot(x,p)

Answer 1

[Matt J]

 p= @(x) (beta/(2*alfa*gamma(1/beta))).*exp(-((abs(x-mean)/alfa).^beta));

 [xx,yy]=ndgrid(-6:0.01:6);

 mask = p(sqrt(xx.^2+yy.^2))

[Mario Trevino]

thanks a lot Matt!