matlab plot rendering problem

Suppose my data has very low discreteness, as given in the attached file

y2_max is x

st20_1 and trend_parabolic are y

I would like to ask how can I draw to increase the contrast between the two Let viewers see the difference

clear all;
clc
clf
load y2_max.mat
load St20_1.mat
load trend_parabolic.mat
plot(y2_max , St20_1)
hold on
plot(y2_max , trend_parabolic)

Answer 1

[dpb]

load https://www.mathworks.com/matlabcentral/answers/uploaded_files/1115780/y2_max.mat

Error using load
Unable to read file 'https://www.mathworks.com/matlabcentral/answers/uploaded_files/1115780/y2_max.mat'. If it is a Version 7 or earlier MAT-file, consider saving your data afresh in Version 7.3
MAT-files to access it from a remote location.

I dunno whassup w/ this last couple days -- too much grief download that many files; please combine them all into one .mat file and also use the -v7.3 switch so folks can read it here.

That aside, a couple suggestions of what you could do although your data are such that the quadratic fits very well so the overlaying of the fit versus the data is going to be present no matter what you do.

One alternative presentation might be

plot(y2_max,St20_1,'x')             % plot the data itself as points only, no line
hold on
plot(y2_max,trend_parabolic)        % then add the fitted line
yyaxis right                        % and subsequently, add the residual on RH axis
resid=max,St20_1-trend_parabolic;   % residuals/differences
plot(y2_max,resid)                  % then add the fitted line

Salt to suit...