also in some cases getting wrong intersection, in remaining getting error of not having unique points(intersect1).
intersection of lines and curves
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SHANTANU KSHIRSAGAR
on 12 May 2020
Commented: Star Strider
on 22 May 2020
i have data in which line is plotted on a signal having pulses. I want to find out all points of intersections between the line and the curve. Right now i am able to get single point of intersection on only one side of pulse. I also need point of intersection on the other side.
Accepted Answer
Star Strider
on 12 May 2020
Try this:
D = load('intersect1.mat');
x_curve = D.x_curve;
y_curve = D.y_curve;
x_line = D.x_line;
y_line = D.y_line;
x_curve(x_curve == 0) = []; % Eliminate Spurious Points
y_curve(y_curve == 0) = []; % Eliminate Spurious Points
zci = @(v) find(v(:).*circshift(v(:), -1, 1) <= 0); % Returns Approximate Zero-Crossing Indices Of Argument Vector (>= R2016b)
icix = zci(y_curve - y_line(1:end-2));
figure
plot(x_curve, y_curve, x_line, y_line)
hold on
plot(x_curve(icix), y_curve(icix), 'dr')
hold off
grid
producing:
The x-values of the intersections are about 0.135 and 0.149. (They are: x_curve(icix).)
The points are dense enough that it is not necessary to interpolate them to get reasonably precise values for the intersections.
.
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More Answers (1)
KALYAN ACHARJYA
on 12 May 2020
Edited: KALYAN ACHARJYA
on 12 May 2020
Have you tried this way?
data1
data2
diff=data1-data2;
small_value=?? % Define small value to deal with samll differenece also
% Make the lower as possible, though ensure that it donot missed the interconnection
idx=find(diff<small_value);
If the data1 and data2 are non floating numbers, you can do the following
idx=find(data1==data2)
10 Comments
Walter Roberson
on 12 May 2020
Do you mean that you are not permitted to use the functions there, or that you have technical problems when you try to use those functions?
If you are not permitted to use the functions there, then I would be concerned that if I were to give you code for this purpose, that you would not be permitted to use it.
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