High pass filter for the values

Hello,

I want to have a high pass filter such that values above zero remain, and the amplitudes of the negative values are somehow reduced as shown in the figure. I am also attaching the data wherein the first coloumn is x-axis and second column is y axis.

Thanks very much in advance.

Answer 1

[Star Strider]

‘I want to have a high pass filter such that values above zero remain, and the amplitudes of the negative values are somehow reduced as shown in the figure’

That is not how a highpass filter works. It passes frequencies above a certain value, not amplitudes.

If you want to reduce the amplitudes of the values less than zero, experiment with this:

D = load('data.txt');
x = D(:,1);
y = D(:,2);

yr = y;
yr(y<0) = -y(y<0).^2;

figure
plot(x, y)
hold on
plot(x, yr)
hold off
grid

Other transformations (or hard limits) could also be appropriate.

[Aristo Pacino]

Perfect! Thanks so very much.

[Star Strider]

As always, my pleasure!