Qubit mixed state density matrix coordinates on a Bloch ball

• I
What are the coordinates on the 3D Bloch ball of a qubit's mixed state of the form:
##\rho=p_{00}|0\rangle \langle 0|+p_{01}|0\rangle \langle 1|+p_{10}|1\rangle \langle 0|+p_{11}|1\rangle \langle 1|##

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Do we have to diagonalize the density matrix everytime and then use the forumla for the coordinates
##(\sum p_i x_i, \sum p_i y_i,\sum p_i z_i)## ?
https://en.wikipedia.org/wiki/Bloch_sphere

Not very practical.

Strilanc
From stackoverflow: "Convert from qubit density matrix to Bloch vector"

Code:
def toBloch(matrix):
[[a, b], [c, d]] = matrix
x = complex(c + b).real
y = complex(c - b).imag
z = complex(d - a).real
return x, y, z
In other words, yes you have to use the formula. But I'm not sure why you think it's impractical... it's just three additions/subtractions.