BUG: PrecisionMvNormalRV missing factor of 1/2 for log determinant in logp function

[ckrapu]

Describe the issue:

At this line,

logp = -0.5 * (k * pt.log(2 * np.pi) + quadratic_form) + logdet

should be

logp = -0.5 * (k * pt.log(2 * np.pi) + quadratic_form + logdet)

Reproduceable code example:

N/A

Error message:

PyMC version information:

5.21.1

Context for the issue:

No response

[ricardoV94]

@ckrapu wanna open a PR by any chance?