plotting new axis given a DCM

Good Morning,

If I am given a coordinate system centered at [0,0,0] and have obtained the cosines of the angles (DCM) how can I apply this to obtain the rotated coordinate system on a plot?

Thanks,

Mel

[Iain]

Why not plot whatever it is that you want to plot on two separate axes?

[Melissa]

I want to show the new x axis with the other coordinate system.

[Iain]

Plot a unit vector on it?

[Melissa]

I would love to but I don't know how to apply it. Say I have a coordinate system centered at [0,0,0] and I want to extend the new x axis starting from that origin uh how about 100 units given a DCM for the new x axis of [.995 .035 .121]. I dont know how to apply the DCM to that current axis to get that new vector.

[Iain]

 OldCords = [0 1;0 0;0 0] %origin, and x = 1 (unit vector)
 NewCords = DCM * OldCords;
 plot3(NewCords(1,:),NewCords(2,:),NewCords(3,:))

[Walter Roberson]

hgtransform() ?

[Melissa]

The DCM should produce a new x axis that is of three rotations right? Shouldn't I have a set of three points that isn't zero?

[Melissa]

Maybe using the quiver function since I thought the DCM was the unit vector if its expressed already in cosines. does this make sense? quiver3(0, 0, 0, .995, .035, .120). Or if I want to extend that 100 units I would just multiply the DCM values by 100?!?

[Iain]

What I gave you was two coordinates, so that you'd get a line starting at the origin, before and after transformation.

Yes, each column of the DCM gives you the corresponding unit vector.

And, for me, its knocking off time...

[Melissa]

Thank you for being patient with me and for your assistance.