Update README.md

add fit description RETC

README.md

@@ -9,13 +9,14 @@ Python package for (unsaturated) soil properties including pedotransfer function
   - Gardner
   - Panday ([Modflow-USG](https://www.gsienv.com/product/modflow-usg/))
 
-This package also contains some datasets with soil properties and parameters:
+This package can fit soil water retention curves and  using least squares (same as [RETC](https://www.pc-progress.com/Documents/programs/retc.pdf)) to measurements.
+
+Measurements for different soil properties and parameters are available from these datasets:
   - [HYDRUS](https://www2.pc-progress.com/downloads/Pgm_Hydrus3D5/HYDRUS_user_Manual_V5.pdf)
   - [VS2D](https://pubs.usgs.gov/wri/1983/4099/report.pdf)
   - Staring Series ([2001](https://edepot.wur.nl/43272) & [2018](https://edepot.wur.nl/512761))
 
-Additionaly there are pedotransfer functions available such for the following soil models:
-
+Additionaly, there are pedotransfer functions implemented such as:
   - Van Genuchten: [Wösten](https://www.sciencedirect.com/science/article/pii/S0016706198001323/pdfft?md5=6844f89c07deb81001c2a6eea6fc9e32&pid=1-s2.0-S0016706198001323-main.pdf)
   - Van Genuchten: [Staring Series](https://edepot.wur.nl/43272)
   - Brooks-Corey: [Cosby](https://hess.copernicus.org/articles/25/2445/2021/hess-25-2445-2021.pdf)
@@ -28,3 +29,8 @@ To get the latest stable version install using:
 To get the development version download the GitHub code to your computer. Use cd to get to the download directory and install using:
 
 `pip install -e .`
+
+
+## Todo
+- [ ] Rosetta Pedotransfer Function
+- [ ] Other soil models such as Haverkamp