dynatopGIS & dynatop

The following schematic outlines the stages resulting a working Dynamic TOPMODEL for a catchment. It highlights where the dynatopGIS and dynatop packages fit into this process.

Schematic of a Dynamic TOPMODEL construction

As we will see in the example the dynatopGIS package can help

• Compute standard variables for classification (such as the topographic index)
• Compute the spatial ordering of the HRUs
• Build classifications of the catchment
• Construct models suitable for dynatop

The dynatop package allows simulation and visualisation of Dynamic TOPMODELs as well as providing some helper for processing time series input data. Although in this training presumes that model for dynatop are generated using dynatopGIS this need not be the case so long as the inputs to dynatop are of the correct format.

Implementation notes

The dynatopGIS and dynatop packages implement structured, object orientated, data flows. The packages are written using the object orientated framework provided by the R6 package. This means that some aspects of working with the objects may appear idiosyncratic for some R users. In this training these problems are largely obscured, except for the call structure. However, before adapting the code, or doing more complex analysis users should read about R6 class objects (e.g. in the R6 package vignettes or in the Advanced R book). One particular gotcha is when copying an object. Using

my_new_object  <-  my_object

creates a pointer, that is altering my_new_object also alters my_object. To create a new independent copy of my_object use

my_new_object  <-  my_object$clone()