Polar to Cartesian coordinates conversion in Keplerian orbit

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Suppose you have an elliptical orbit like this one here. What I have are 2D polar coordinates for any point on it, and the inclination of the ellipse's plane with regard to the reference plane. What I want to do is to obtain the Cartesian coordinates of any such point.

So, what I have given is:

d - distance from the primary, a - azimuth on the ellipse's plane (true anomaly), i - inclination of the ellipse's plane to the reference plane.

From this, I want to get the x, y, z coordinates. According to various sources, the formulas are:

x = d*sin(theta)*cos(phi)

y = d*sin(theta)*sin(phi)

z = d*cos(theta)

Of these, I seem only to have the d. How do I divine theta and phi from the available data?