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% Normal log-spaced vector
x1 = logspace(1, 2, 10);
% Create inverse log space
delta = diff(x1);
delta = fliplr(delta);
% Inversely log-spaced vector
x2 = [10, 10+cumsum(delta)];
% Check!
figure
plot(x1, 'o')
hold on
plot(x2, 'v')
legend({'x1', 'x2'}, 'Location', 'best')
