diff --git a/src/DataFilter.cpp b/src/DataFilter.cpp
index 550d770f7..82df1bcdc 100644
--- a/src/DataFilter.cpp
+++ b/src/DataFilter.cpp
@@ -243,6 +243,7 @@ void Leaf::validateFilter(DataFilter *df, Leaf *leaf)
             QRegExp bestValidSymbols("^(apower|power|hr|cadence|speed|torque|vam|xpower|np|wpk)$", Qt::CaseInsensitive);
             QRegExp tizValidSymbols("^(power|hr)$", Qt::CaseInsensitive);
             QRegExp configValidSymbols("^(cp|w\\'|pmax|cv|d\\'|scv|sd\\'|height|weight|lthr|maxhr|rhr|units)$", Qt::CaseInsensitive);
+            QRegExp constValidSymbols("^(e|pi)$", Qt::CaseInsensitive); // just do basics for now
             QString symbol = leaf->series->lvalue.n->toLower();
 
             if (leaf->function == "sts" || leaf->function == "lts" || leaf->function == "sb" || leaf->function == "rr") {
@@ -262,6 +263,19 @@ void Leaf::validateFilter(DataFilter *df, Leaf *leaf)
                 if (leaf->function == "config" && !configValidSymbols.exactMatch(symbol))
                     DataFiltererrors << QString(QObject::tr("invalid data series for config(): %1")).arg(symbol);
 
+                if (leaf->function == "const") {
+                    if (!constValidSymbols.exactMatch(symbol))
+                        DataFiltererrors << QString(QObject::tr("invalid literal for const(): %1")).arg(symbol);
+                    else {
+
+                        // convert to a float
+                        leaf->type = Leaf::Float;
+                        leaf->lvalue.f = 0.0L;
+                        if (symbol == "e") leaf->lvalue.f = MATHCONST_E;
+                        if (symbol == "pi") leaf->lvalue.f = MATHCONST_PI;
+                    }
+                }
+
                 if (leaf->function == "best" || leaf->function == "tiz") {
                     // now set the series type used as parameter 1 to best/tiz
                     leaf->seriesType = nameToSeries(symbol);
diff --git a/src/DataFilter.h b/src/DataFilter.h
index 9b06c67a1..51398631f 100644
--- a/src/DataFilter.h
+++ b/src/DataFilter.h
@@ -123,4 +123,20 @@ class DataFilter : public QObject
 };
 
 extern int DataFilterdebug;
+
+// some constants we provide to help accessed via const(name)
+#define MATHCONST_E 		    2.718281828459045235360287471352662498L /* e */
+#define MATHCONST_LOG2E 	    1.442695040888963407359924681001892137L /* log_2 e */
+#define MATHCONST_LOG10E 	    0.434294481903251827651128918916605082L /* log_10 e */
+#define MATHCONST_LN2 		    0.693147180559945309417232121458176568L /* log_e 2 */
+#define MATHCONST_LN10 	    2.302585092994045684017991454684364208L /* log_e 10 */
+#define MATHCONST_PI 		    3.141592653589793238462643383279502884L /* pi */
+#define MATHCONST_PI_2 	    1.570796326794896619231321691639751442L /* pi/2 */
+#define MATHCONST_PI_4 	    0.785398163397448309615660845819875721L /* pi/4 */
+#define MATHCONST_1_PI 	    0.318309886183790671537767526745028724L /* 1/pi */
+#define MATHCONST_2_PI 	    0.636619772367581343075535053490057448L /* 2/pi */
+#define MATHCONST_2_SQRTPI 	1.128379167095512573896158903121545172L /* 2/sqrt(pi) */
+#define MATHCONST_SQRT2 	    1.414213562373095048801688724209698079L /* sqrt(2) */
+#define MATHCONST_SQRT1_2 	    0.707106781186547524400844362104849039L /* 1/sqrt(2) */
+
 #endif
diff --git a/src/DataFilter.l b/src/DataFilter.l
index 6ed69b88b..331d31456 100644
--- a/src/DataFilter.l
+++ b/src/DataFilter.l
@@ -46,6 +46,8 @@
 [Ee][Nn][Dd][Ss][Ww][Ii][Tt][Hh]            DataFilterlval.op = ENDSWITH; return ENDSWITH;
 [Cc][Oo][Nn][Tt][Aa][Ii][Nn][Ss]            DataFilterlval.op = CONTAINS; return CONTAINS;
 
+                                           /* functions identified by name in the lexer is probably
+                                              going to limit us in the future */
 [Bb][Ee][Ss][Tt]                           strcpy(DataFilterlval.function, "best"); return BEST;
 [Tt][Ii][Zz]                               strcpy(DataFilterlval.function, "tiz"); return TIZ;
 [Ll][Tt][Ss]                               strcpy(DataFilterlval.function, "lts"); return LTS;
@@ -53,6 +55,7 @@
 [Ss][Bb]                                   strcpy(DataFilterlval.function, "sb"); return SB;
 [Rr][Rr]                                   strcpy(DataFilterlval.function, "rr"); return RR;
 [Cc][Oo][Nn][Ff][Ii][Gg]                   strcpy(DataFilterlval.function, "config"); return CONFIG;
+[Cc][Oo][Nn][Ss][Tt]                       strcpy(DataFilterlval.function, "const"); return CONST;
 
 "&&"                                        DataFilterlval.op = AND; return AND;
 [Aa][nN][Dd]                                DataFilterlval.op = AND; return AND;
diff --git a/src/DataFilter.y b/src/DataFilter.y
index 83165d39a..0c354c133 100644
--- a/src/DataFilter.y
+++ b/src/DataFilter.y
@@ -54,7 +54,7 @@ extern Leaf *root; // root node for parsed statement
 
 // Constants can be a string or a number
 %token <leaf> DF_STRING DF_INTEGER DF_FLOAT
-%token <function> BEST TIZ STS LTS SB RR CONFIG
+%token <function> BEST TIZ STS LTS SB RR CONFIG CONST
 
 // comparative operators
 %token <op> Q COL
@@ -210,6 +210,11 @@ value : symbol                      { $$ = $1; }
                                         $$->series = $3;
                                         $$->lvalue.l = NULL;
                                       }
+      | CONST '(' symbol ')'       {   $$ = new Leaf(); $$->type = Leaf::Function;
+                                        $$->function = QString($1);
+                                        $$->series = $3;
+                                        $$->lvalue.l = NULL;
+                                      }
       ;
 
 %%
diff --git a/src/LTMTool.cpp b/src/LTMTool.cpp
index ff4bfa20e..1690425ae 100644
--- a/src/LTMTool.cpp
+++ b/src/LTMTool.cpp
@@ -1748,6 +1748,8 @@ EditMetricDetailDialog::EditMetricDetailDialog(Context *context, LTMTool *ltmToo
     list << "config(maxhr)";
     list << "config(rhr)";
     list << "config(units)";
+    list << "const(e)";
+    list << "const(pi)";
     list << "ctl";
     list << "tsb";
     list << "atl";