Add item to TODO list

README.md

@@ -74,3 +74,4 @@ been corrected for systematic errors, so actual elevations should be taken from
 - [ ] Implement data/interim/*.csv file checking using py.test. Check for correct columns, number of nans etc. Testing of code is probably a lower priority than just checking the interim data files at the moment.
 - [ ] Investigate using [modin](https://github.com/modin-project/modin) to help speed up analysis.
 - [ ] Need to think about how relative imports are handled, see [here](https://chrisyeh96.github.io/2017/08/08/definitive-guide-python-imports.html). Maybe the click CLI interface should be moved to the `./src/` folder and it can import all the other packages?
+- [ ] Simplify runup_models in Stockdon06 - we should really only have one function for each runup model. Need to make it work with individual values or entire dataframe. Use (np.maskedarray)[https://docs.scipy.org/doc/numpy-1.15.0/reference/maskedarray.generic.html]