How do you transfer spherical coordinate into cartesian and vice versa?

Answer 1

If spherical coords are r and theta, then

x = r*cos(theta)

and

y = r*sin(theta)

Conversely,

r = sqrt(x2 + y2)

and

theta = arctan(y/x) provided x is not zero.

and

theta = 90 deg when x = 0