Ottar

Version following initial completion of methods section of paper and distribution to coauthors.

* Major Enhancements
* Bed-load diffusion: Full overhaul. Stochastic lateral motion due to particle collisions
* Noncohesive erosion: time of flight, and therefore, particle step length. This makes $k_E$ dimensionless.
* Double Manning can now use hydraulic radius or depth; the latter uses the wide-channel assumption.
* Minor enhancements
* Critical Shields stress [(`tau_star_c_sed`) is now user-definable](https://github.com/MNiMORPH/OTTAR/commit/003bbe4be53f542d4e9ffb960c72a4f979b8f676)
* Lump all shear-stress and shear-velocity variable computations into a single function in which they are updated; call this at an early point while updating width. See: [Centralize update of stress, shear, and turbulence variables: Prior to widening, narrowing calculations.](https://github.com/MNiMORPH/OTTAR/commit/94504f0e23024fcc71543841dd35830b3bdfef21)
* [Plot db_dt__day__narrowing_series as negative.](https://github.com/MNiMORPH/OTTAR/commit/0922b3aec35684c6df99ae1403ab49778b04f893)
* [Add legend_loc option for plotting; legend fontsize=12](https://github.com/MNiMORPH/OTTAR/commit/c1a2ba8162de5445edd426e513eb67527e8684c3)
* Fixes
* Plotting works with updated Pandas (indexing deprecation)
* Fix function `compute__u_star__tau_bed`: Remove 1/2 power from `self.tau_star_bed` calculation in `(self.rho_s - self.rho)`.
* [Let self.tau_star_bank not be defined if D is None.](https://github.com/MNiMORPH/OTTAR/commit/b57cdb1be715624a84a413c0d306b12e45e43a30)

Version for AGU 2022 and close to final for the paper submission

* Allow nonuniform dt
* Narrowing by (with separate functions):
* Suspended load
* Bed load
* Widening by (with separate functions):
* Cohesive-bank erosion
* Noncohesive-sediment entrainment
* Updated README table of inputs
* Cimarron Flood example test

* Widening with cohesive and noncohesive banks: Chooses the slower of the two, if both available, as rate-limiting process
* Narrowing via bedload and suspended load

* Fully functional but currently designed for cohesive banks only.
* Cleaned repository
* Improved physical basis for channel narrowing
* Prepared for integration with PyPI

Version as of **AGU 2021**

* Double-Manning rating-curve relationship to incorporate field data and overbank flow
* Externally set roughness
* Cohesive/noncohesive instead of detachment-/transport-limited
* Initialize time series of flow data
* Gary Parker (1978) shear stress distribution and channel geometry for even shear stress across the whole wall in the bank region
* Channel narrowing through lateral diffusion of sediment and disentrainment in the near-bank regions

* Fully functional
* Object oriented
* Does not spread high flows overbank; instead, concentrates them in the channel and on wall stress