%% Determine Disk Size for Symmetric Gain Variation
% Compute the disk size α of the disk that represents a gain variation of ±6 dB, that is, gain that can increase or decrease by about a factor of 2.

GM = db2mag(6);
[alpha,E] = gm2dm(GM)

%
% For symmetric gain variations, the eccentricity E is 0. Examine the disk corresponding to this gain variation.

diskmarginplot(alpha,E,'disk')

%  The disk that captures gain variations of a factor of two in either direction also models phase variations of ±37°.
%
% Copyright 2019 The MathWorks, Inc.