+ 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;