Sum of both negative - positive part of a Peak

Question

abaza 2019-11-25

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/493073-sum-of-both-negative-positive-part-of-a-peak

编辑： Star Strider 2019-11-25

Dear ALL,

I have a peak that I woud like to take the integral of it, however, this peak has a positive (> 0 baseline) and negative part (< 0 beaseline).

So, is it any function in MATLAB that automatically sums both parts?

Please see attached the example...

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Star Strider 2019-11-25

1
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/493073-sum-of-both-negative-positive-part-of-a-peak#answer_403247

在 MATLAB Online 中打开

Try this:

x = linspace(6.622, 9.644);
y = exp(-(x-mean(x)).^2/0.5) - 0.1;
Lv = y>=0;
PosPart = trapz(x(Lv), y(Lv))
NegPart = trapz(x(~Lv), y(~Lv))
SumParts = PosPart - NegPart
figure
plot(x, y)

Experiment to get different results.

2 个评论
显示无隐藏无

abaza 2019-11-25

Thank you so much for your quick response!

I will try to implement what you suggested in my "real work data", and I will come back to you for "accepting you answer"!

Cheers!

Star Strider 2019-11-25

编辑：Star Strider 2019-11-25

在 MATLAB Online 中打开

My pleasure!

EDIT — (25 Nov 2019 at 22:10)

Depending on what you want to do, this may be more accurate:

Lv = y>=0;
PosPart = trapz(x(Lv), y(Lv))
LT0 = trapz(x(~Lv), ones(size(x(~Lv)))*min(y))
NegPart = LT0 - trapz(x(~Lv), y(~Lv))
SumParts = PosPart - NegPart

请先登录，再进行评论。