The easiest way to add a line of determined slope to a loglog

Hello! I have a graph made by

loglog();

and I would like to add determined slope. I am not saying about linear fit or trend. I am interested to add a line of determined slope to a loglog.

Imagine that we have this:

clear;clc;clf;
f= ;  % some argument input 
Spectrum_Power =;%  somefunction of f  
loglog(f,Spectrum_Power);
grid on;

And how to add a slope of -5/3 to this plot? Thanks in advance!

Answer 1

[David Goodmanson]

Hello Ivan, A straight line of slope -5/3 on a loglog plot has the form log(y) = (-5/3)*log(x) + b with an arbitrary constant b. Exponentiating both sides gives

y = c*x.^(-5/3);

with a constant c = exp(b) which is arbitrary except that c > 0. So the form above with any positive c will give the requisite straight line on a loglog plot.

[Ivan Volodin]

Thank you!