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Task/Averages-Arithmetic-mean/GFA-Basic/averages-arithmetic-mean.gfa

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+DIM a%(10)
+FOR i%=0 TO 10
+  a%(i%)=i%*2
+  PRINT "element ";i%;" is ";a%(i%)
+NEXT i%
+PRINT "mean is ";@mean(a%)
+'
+FUNCTION mean(a%)
+  LOCAL i%,size%,sum
+  ' find size of array,
+  size%=DIM?(a%())
+  ' return 0 for empty arrays
+  IF size%<=0
+    RETURN 0
+  ENDIF
+  ' find sum of all elements
+  sum=0
+  FOR i%=0 TO size%-1
+    sum=sum+a%(i%)
+  NEXT i%
+  ' mean is sum over size
+  RETURN sum/size%
+ENDFUNC