Display negative values on logarithmic graph

Hi, I want to plot a set of data where the values oscillates around 0 but the amplitude decays exponentially. It is normally plotted with two different logarithmic yaxis on top of each other. With the lower one in reverse order. Can that be done in Matlab?

 Accepted Answer

Plot the logarithm of the absolute value of y multiplied by sign of y, and the change labels:
x = linspace(0,3,10000);
y = 1e6*exp(-x).*(sin(10*x)-0.5);
plot(x,y)
figure
Y = sign(y).*log10(abs(y));
plot(x,Y,'.')
yl = get(gca,'ytick');
set(gca,'yticklabel',sign(yl).*10.^abs(yl))

2 Comments

Thank you, that's just what I wanted.
Ainray
Ainray on 22 Mar 2023
Edited: Ainray on 22 Mar 2023
It give wrong ticks

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More Answers (0)

Asked:

on 8 Mar 2012

Edited:

on 22 Mar 2023

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