finding slope of a signal

33 次查看（过去 30 天）

显示更早的评论

Sara 2018-9-6

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/417802-finding-slope-of-a-signal

评论： Dimitris Kalogiros 2018-9-6

采纳的回答： Dimitris Kalogiros

Hello. I have two signals (according to figure) and I want to find the slop of each signal.

Thanks for further help.

2 个评论
显示无隐藏无

jonas 2018-9-6

Well, as you can see the slope is varying. What exactly are you looking for? The trend? The change in every point?

Sara 2018-9-6

sorry for the poor explanation. I want to get the trend.

请先登录，再进行评论。

请先登录，再回答此问题。

采纳的回答

Dimitris Kalogiros 2018-9-6

1
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/417802-finding-slope-of-a-signal#answer_335702

在 MATLAB Online 中打开

A script that calculates mean slope :

clc; clear; close all;
%%generate input signal
x=0:1:1500;
y=(-0.002*x+3)+abs(sin(2*pi*.002*x))+0.2*sin(2*pi*.01*x);
figure; plot(y, '-b'); zoom on; grid on;
xlabel('x'); title('input signal y'); hold on;
%%first order aproximation
p=polyfit(x,y,1);
polyValues=p(1)*x+p(2);
plot(polyValues,'--r');
legend('input signal', 'first order approximation');
%%slope detection
fprintf(' mean slope = %f \n', p(1));

Of course, I had to generate a signal similar to what you presented at your question.

If you run the script you will receive the following:

4 个评论
显示 2更早的评论隐藏 2更早的评论

jonas 2018-9-6

You can draw a line from the start point to the end point, but what's the point of that? It's certainly not indicative of future values.

Dimitris Kalogiros 2018-9-6

@Sara , If the end point of the red line and the end point of the signal are the same , then you might have a significant error on what you have calculated as "mean slope". I believe, the method I used for the calculation of the "red line" is (probably) the best one.

请先登录，再进行评论。