- #1
birdhen
- 35
- 0
Hi there,
I am getting confused about how to work this out.
I know that to convert cartesian coordinates to spherical coordinates you can use:
theta=arccos(z)
phi=arcsin(y/sin(theta))
my problem is that I have a list of coordinates, let's call them THETA and PHI. I change them into X,Y,Z and then rotate them by 2 Euler angles.
THETA is in the range(0->2pi)
PHI is in the range (-pi/2->pi/2).
the problem is once I have completed the transforms I want the new value theta, As it is found using arccos the value returned is only in the range 0->pi, the values come back between 0 and 180, where as the THETA values are between 0 and 360, and therefore I want my transformed values to be in the range 0 to 360. I think I need to use quadrants but I have been searching the internet and can't find the info I need.
Any help would be greatly appreciated.
I am getting confused about how to work this out.
I know that to convert cartesian coordinates to spherical coordinates you can use:
theta=arccos(z)
phi=arcsin(y/sin(theta))
my problem is that I have a list of coordinates, let's call them THETA and PHI. I change them into X,Y,Z and then rotate them by 2 Euler angles.
THETA is in the range(0->2pi)
PHI is in the range (-pi/2->pi/2).
the problem is once I have completed the transforms I want the new value theta, As it is found using arccos the value returned is only in the range 0->pi, the values come back between 0 and 180, where as the THETA values are between 0 and 360, and therefore I want my transformed values to be in the range 0 to 360. I think I need to use quadrants but I have been searching the internet and can't find the info I need.
Any help would be greatly appreciated.