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How to extract the scatter data based on a function

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joynjo
joynjo on 18 Jul 2018
Edited: joynjo on 21 Jul 2018
I have a scatter data as attached image follows, how to sign the data outside the function line with '1' and the data under the function line with '0' then save it into one variable?
  1 Comment
joynjo
joynjo on 21 Jul 2018
Up, I am still waiting for anyone who can help me solve this problem, thanks

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Answers (1)

Image Analyst
Image Analyst on 18 Jul 2018
I have no idea what "sign the data" with 0 or 1 means, but to get the data under and above/outside the function, try something like this
indexesUnderTheCurve = false(1, length(x));
for k = 1 : length(x)
thisX = x(k);
thisY = y(k);
curveY = YourFunction(thisX); % Plug the x into your custom function
if thisY < curveY
% Under the curve
indexesUnderTheCurve(k) = true;
end
end
xUnder = x(indexesUnderTheCurve);
yUnder = y(indexesUnderTheCurve);
xOver = x(~indexesUnderTheCurve);
yOver = y(~indexesUnderTheCurve);
  5 Comments
joynjo
joynjo on 21 Jul 2018
please kindly find m file for my QDA classification as attached included with the related files.

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