# Measurements¶

A measurement can be defined as a function

$\mu : \Sigma \rightarrow \text{Pos}(\mathcal{X})$

satisfying

$\sum_{a \in \Sigma} \mu(a) = \mathbb{I}_{\mathcal{X}}$

where $$\Sigma$$ represents a set of measurement outcomes and where $$\mu(a)$$ represents the measurement operator associated with outcome $$a \in \Sigma$$.

## Operations on Measurements¶

 toqito.measurement_ops.measure(measurement, …) Determine probability of obtaining a measurement outcome applied to state.

## Properties of Measurements¶

 toqito.measurement_props.is_povm(mat_list) Determine if a list of matrices constitute a valid set of POVMs [WikPOVM].