Vector3D angleTo function returning wrong result

[j.han97]

Hi all,

Just a very simple problem here. I have defined two vectors, which are the unit vectors in x- and z-directions respectively.

vec_1 = adsk.core.Vector3D.create(1, 0, 0)
vec_2 = adsk.core.Vector3D.create(0, 0, 1)

I expected the angle between these vectors are 90 degrees, which is 0.7854 radian. However, when I used the angleTo function to obtain the result,

vec_1.angleTo(vec_2)

It returned 1.5708 (radian), which is 180 degrees.

Did I miss something or could anyone tell me what is wrong here?

Thank you very much in advance.

[BrianEkins · Accepted solution]

You're just a bit mixed up on the relationship between degrees and radians.  π radians (3.14159) = 180 degrees, so the answer you're getting of 1.5708 radians is 90 degrees.

[j.han97]

Wow, what a stupid mistake from me. Thank you so much Brian.