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Index Index

Last edited: August 8, 2025

Here’s a list of all indexes:

This should be reflected on a fancier way on my home page.

inductor

Last edited: August 8, 2025

voltage across a inductor

\begin{equation} V = \epsilon = -L \dv{I}{t} \end{equation}

this is kind of a formulation of faraday’s law.

\begin{equation} I(t) = \frac{V_0}{R_1} (1-e^{\frac{-t}{\frac{L}{R}}}) \end{equation}

energy stored in an inductor

\begin{equation} E = \frac{1}{2} LI^{2} \end{equation}

inference

Last edited: August 8, 2025

inference is the act of updating the distribution of a random variable based on distribution of actually observed variables:

\begin{equation} P(X|Y) \end{equation}

where \(Y\) is observed, and we want to know how likely \(X\) would therefore be.

We call the set \(X\) the “query variables”, \(Y\) as “evidence varibales”, and anything that we didn’t use which connects the two variables as “hidden variables”.

If things are not in the right order of \(X\) and \(Y\), consider the Bayes rule.

Inference for Gaussian Models

Last edited: August 8, 2025

If we know that \(a,b\) are both Gaussian distributions, then we have that:

\begin{equation} \mqty[a \\ b] \sim \mathcal{N} \qty(\mqty[\mu_{a} \\mu_{b}], \mqty[A & C \\ C^{T} & B]) \end{equation}

whereby:

To perform inference:

\begin{equation} p(a|b) = \mathcal{N}(a | \mu_{a|B}, \Sigma_{a|b}) \end{equation}

wherby:

\begin{equation} \mu_{a|b} = \mu_{a} + CB^{-1}(b-\mu_{b}) \end{equation}

inflectional words

Last edited: August 8, 2025