calculate the angle between a line (between two points) and the perpendicular line
4 views (last 30 days)
Show older comments
if point1 is a(x1,y1) and point 2 is b(x2,y2). I want to draw a vertical from point b in order to calculate the angle between the line ab and the verticle line.
I wrote this code but I think i can't get the verticle line correctly as I got the same value of the angle and i'm sure the angle value is not the same.
for i=1:size(a,1)
angle = atand(b(1,i) - a(1,i))-(b(2,i) - a(2,i)))
end
any one can help me please?
3 Comments
Geoff Hayes
on 20 Mar 2019
Amneh's answer moved here
I'm using a loop because points a and b are moving and changing their positions. I want to caluctae the angle for every fram. I assumed that the vericle line is between (point a (x1,y1) and Point (x1,y2))
Geoff Hayes
on 20 Mar 2019
I assumed that the vericle line is between (point a (x1,y1) and Point (x1,y2)) Can you provide a picture? I don't understand how the vertical line is between (x1,y1) and (x1,y2) (or do you mean (x2,y2) for the second one?). Also I thought I want to draw a vertical from point b which suggests that the vertical line is drawn from point b and is not in between the two points. Please clarify.
Accepted Answer
Jan
on 20 Mar 2019
Maybe you mean:
angle = atand(b(1,:) - a(1,:)) - (b(2,:) - a(2,:)))
% ^???
without a loop. But here the number of parentheses does not match. I'm not sure which problem you want to solve.
0 Comments
More Answers (2)
Geoff Hayes
on 20 Mar 2019
Edited: Geoff Hayes
on 20 Mar 2019
Amneh - if a is (x1,y1) and b is (x2,y2) then let c be (x2,y1). With these three points, you should have a right-angled triangle. We can determine the opposite and adjancent as
opposite = abs(a(1) - c(1));
adjacent = abs(c(2) - b(2));
and so the angle is
myAngleDegrees = atand(opposite / adjacent);
(I think!)
0 Comments
See Also
Categories
Find more on Time Series Objects in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!