Manage noise when running circuits

Running circuits on quantum hardware devices means dealing with the noise those devices introduce to the computation. Cirq provides the following ways of managing that noise, to improve the quality of the measured results.
Noise models and channels and what types of error they replicate.

Characterization and compensation

Characterize the error a device is exhibiting, then compensate for that error by changing the circuit or reinterpreting the results.
A characterization benchmarking method using cross entropy.

Visualizing noise

Graphing and plotting methods for visualizing noise.
Functions to plot noise characteristics across a 2D grid device.