Normalize and integrate a curve
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Hello!
If I want to normalize and integrate this curve, how should I do it?
![](https://www.mathworks.com/matlabcentral/answers/uploaded_files/276356/image.jpeg)
clc
clear all
Data1=importdata('J30.txt');
x=Data1(:,1);
y=Data1(:,2);
plot(x,y)
2 Comments
John D'Errico
on 10 Mar 2020
trapz won't integrate it? Gosh, I thought it was supposed to do that.
What does normalize mean to you? Divide by the integral perhaps?
Answers (1)
Image Analyst
on 10 Mar 2020
Try this:
% Initialization steps.
clc; % Clear the command window.
close all; % Close all figures (except those of imtool.)
clear; % Erase all existing variables. Or clearvars if you want.
workspace; % Make sure the workspace panel is showing.
format long g;
format compact;
fontSize = 20;
Data1=importdata('J30.txt');
x=Data1(:,1);
y=Data1(:,2);
% Plot original data.
subplot(3, 1, 1);
plot(x, y, 'LineWidth', 2);
grid on
title('Original data', 'FontSize', fontSize);
% Normalize by dividing by y Max
y2 = y / max(y);
% Plot normalized data.
subplot(3, 1, 2);
plot(x, y2, 'LineWidth', 2);
grid on
title('Normalized by Max Y signal', 'FontSize', fontSize);
% Find the area under the original y curve
area = trapz(y)
% Normalize by dividing by y Max
y3 = y / area;
area3 = trapz(y3)
% Plot normalized data.
subplot(3, 1, 3);
plot(x, y3, 'LineWidth', 2);
grid on
title('Normalized by Area under the curve', 'FontSize', fontSize);
![](https://www.mathworks.com/matlabcentral/answers/uploaded_files/276369/image.png)
7 Comments
Image Analyst
on 10 Mar 2020
We don't know exactly what you want. Only you know that. I made two guesses as to what you possibly might want. Does any of them look like what you might want?
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