Merge pull request #1 from ajdawson/shallow-water

Add shallow water example code

README.rst

@@ -4,5 +4,12 @@ Reduced precision emulator examples
 The intent of this repository is to collect useful examples of how rpe_ can be
 used to perform numerical experiments with reduced floating-point precision.
 
+Examples:
+---------
+
+* shallow_water:
+
+  A shallow-water equation model on an Arakawa C-grid
+
 
 .. _rpe: http://github.com/aopp-pred/rpe

shallow_water/README.rst

@@ -0,0 +1,26 @@
+Shallow water equations on an Arakawa C-grid
+============================================
+
+These examples use rpe_ to investigate the performance of a shallow water
+equation model defined on an Arakawa C-grid. These model configurations are
+described in Dawson and Düben (2016).
+
+Model configurations
+--------------------
+
+Source code for the following model configurations is provided:
+
+* ``sw_ref.f90``:
+
+  A reference double-precision implementation
+
+* ``sw_reduced.f90``:
+
+  A version with a uniform reduced floating-point precision for all variables
+
+* ``sw_codesigned.f90``:
+
+  A co-designed half-precision version that uses half-precision for computing
+  RHS terms and double-precision for time-stepping update operations
+
+.. _rpe: http://github.com/aopp-pred/rpe