Added AVG function to CDEF language. Martin Sperl martin sperl.org

[rrdtool.git] / src / rrd_rpncalc.c

diff --git a/src/rrd_rpncalc.c b/src/rrd_rpncalc.c
index 104ea8f..3753c0f 100644 (file)
--- a/src/rrd_rpncalc.c
+++ b/src/rrd_rpncalc.c
@@ -161,6 +161,7 @@ void rpn_compact2str(rpn_cdefds_t *rpnc,ds_def_t *ds_def,char **str)
          add_op(OP_TREND,TREND)
          add_op(OP_RAD2DEG,RAD2DEG)
          add_op(OP_DEG2RAD,DEG2RAD)
+         add_op(OP_AVG,AVG)
 #undef add_op
               }
     (*str)[offset] = '\0';
@@ -338,6 +339,7 @@ rpn_parse(void *key_hash,const char *const expr_const,long (*lookup)(void *,char
        match_op(OP_TREND,TREND)
        match_op(OP_RAD2DEG,RAD2DEG)
        match_op(OP_DEG2RAD,DEG2RAD)
+       match_op(OP_AVG,AVG)
 #undef match_op
 
 
@@ -755,6 +757,28 @@ rpn_calc(rpnp_t *rpnp, rpnstack_t *rpnstack, long data_idx,
                        rpnstack -> s[--stptr] = DNAN;
                }
                break;
+           case OP_AVG:
+               stackunderflow(0);
+                {
+                   int i=rpnstack -> s[stptr--];
+                   double sum=0;
+                   int count=0;
+                   stackunderflow(i-1);
+                   while(i>0) {
+                     double val=rpnstack -> s[stptr--];
+                     i--;
+                    if (isnan(val)) { continue; }
+                     count++;
+                     sum+=val;
+                   }
+                   // now push the result bavk on stack
+                   if (count>0) {
+                     rpnstack -> s[++stptr]=sum/count;
+                   } else {
+                     rpnstack -> s[++stptr]=DNAN;
+                   }
+                }
+                break;
            case OP_END:
                break;
        }