create point betweem two points

Hi every one

I have two points, for example

(2,5)-(10,15)... how can I create a new point between them???

thanks a loot

majid

Answer 1

[Walter Roberson]

NumberNewPoints = 3;
xvals = linspace(2, 10, NumberNewPoints+2);
yvals = linspace(5, 15, NumberNewPoints+2);
pts = [xvals(:), yvals(:)];

Now the points are the rows.

[Majid Al-Sirafi]

thank you dear walter

now how can I move the created points ( for example i want to move one created point) between two original points

thanks dear

[Walter Roberson]

Which mechanism were you thinking of for moving the points?

[Majid Al-Sirafi]

dear walter

the mechanism is straight moving (that means the created points move between (2,5) and (10,15) and do not exceed them)

thanks dear

[Walter Roberson]

Let the original point be (x1,y1) and the final point be (x2,y2), and let t be a proportion of the time for the movement (i.e. t=0 when at the starting point, t=1 when at the ending point.) Then,

newpoints = (x1(:) + (x2(:)-x1(:)) .* t, y1(:) + (y2(:)-y1(:)) .* t]

[Majid Al-Sirafi]

please dear let dear apply the equation with the following data let p1(2,5) and p2(10,15) and we want to move p1 by 1 time to p2 so,

newpoints = [2 + (10-2) .*2, 5 + (15-5) .*2]

newpoints = 18 25

         x=18 and y=25 ... is this ok ???
thanks dear

thanks a lot dear

[Walter Roberson]

You used 2 for your time t, not 1. t should be the portion along the line segment that you want, not the absolute time.

If you are starting at time 0 and ending at time Tmax, then the "t" of the equation should be the current time divided by Tmax:

newpoints = (x1(:) + (x2(:)-x1(:)) .* T/Tmax, y1(:) + (y2(:)-y1(:)) .* T/Tmax]

For example if you are at time T now and your last time for the movement is Tmax = 7.3, then you would have

newpoints = (x1(:) + (x2(:)-x1(:)) .* T/7.3, y1(:) + (y2(:)-y1(:)) .* T/7.3]

[Majid Al-Sirafi]

Please dear walter

apply that with the actual values please I have p1(2,5) and p2(10,15) and i want to move from p1 to p2, apply that with your equation, and what the new value of x and y

[Image Analyst]

Walter just loves it when people call him dear. ;-)

http://www.mathworks.com/matlabcentral/answers/24179#comment_53040

[Walter Roberson]

x = 2 + 8 .* T/Tmax;
y = 5 + 10 .* T/Tmax;

Where T is the time since the start, and Tmax is the time at which you want to reach the second point.

[Majid Al-Sirafi]

dear watler according to your code

NumberNewPoints = 3;

xvals = linspace(2, 10, NumberNewPoints+2);

yvals = linspace(5, 15, NumberNewPoints+2);

pts = [xvals(:), yvals(:)];

but I choose NumberNewPoints = 1;

so, the new created point is (6,10) how can I move this created point between p1(2,5) and p2(10,5).. that means i want to move this created point to p1 at first state , and move the created point to p2 at a second state,and the movement time is 2. But this movement do not exceed P1 and p2

thanks a lot

[Walter Roberson]

pts(1,:)   %x,y for starting point
pts(2,:)   %x,y for intermediate point
pts(3,:)   %x,y for final point

Answer 2

[Andrei Bobrov]

out = ([10,15]-[2,5])*(2*rand-1)+[2,5]