DataFilter - store/fetch values

.. saves/loads values to athlete global area, particularly useful when
   modelling as you can save away parameter estimates that may have
   been expensive to compute, and re-use them across series in a
   user chart.

.. they are not saved across restarts, but we could fix that later if
   they become more useful

.. store("name", value) and fetch("name"). if the named value does
   not exist 0 is returned.

[publish binaries]

src/Core/Athlete.h

@@ -20,6 +20,7 @@
 #define _GC_Athlete_h 1
 
 #include "Measures.h"
+#include "DataFilter.h"
 
 #include <QDir>
 #include <QSqlDatabase>
@@ -135,6 +136,9 @@ class Athlete : public QObject
         // named filters / queries
         NamedSearches *namedSearches;
 
+        // DataFilter global storage/cache
+        QMap<QString,Result> dfcache;
+
         Context *context;
 
         // ride collection

src/Core/DataFilter.cpp

@@ -320,6 +320,12 @@ static struct {
                        // kind of interpolation applied (resample/interpolate are available to
                        // do that if needed.
 
+    { "store", 2 },    // store("name", value) stores a global value that can be retrieved via
+                       // the fetch("name") function below. Useful for passing data across data series
+                       // in a user chart.
+    { "fetch", 1 },    // fetch("name") retrieves a value previously stored returns 0 if the value
+                       // is not in the athlete store
+
     // add new ones above this line
     { "", -1 }
 };
@@ -4649,6 +4655,28 @@ Result Leaf::eval(DataFilterRuntime *df, Leaf *leaf, Result x, long it, RideItem
             return Result(count);
         }
 
+        // store/fetch from athlete storage
+        if (leaf->function == "store") {
+            // name and value in parameter 1 and 2
+            QString name= eval(df, leaf->fparms[0],x, it, m, p, c, s, d).string();
+            Result value= eval(df, leaf->fparms[1],x, it, m, p, c, s, d);
+
+            // store it away
+            m->context->athlete->dfcache.insert(name, value);
+
+            return Result(0);
+        }
+
+        if (leaf->function == "fetch") {
+            // name and value in parameter 1 and 2
+            QString name= eval(df, leaf->fparms[0],x, it, m, p, c, s, d).string();
+
+            // store it away
+            Result returning = m->context->athlete->dfcache.value(name, Result(0));
+
+            return returning;
+        }
+
         // access user chart curve data, if it's there
         if (leaf->function == "curve") {