langs a-z

Task/Averages-Arithmetic-mean/UnixPipes/averages-arithmetic-mean.unixpipes

@@ -0,0 +1,22 @@
+term() {
+   b=$1;res=$2
+   echo "scale=5;$res+$b" | bc
+}
+
+sum() {
+  (read B; res=$1;
+  test -n "$B" && (term $B $res) || (term 0 $res))
+}
+
+fold() {
+  func=$1
+  (while read a ; do
+      fold $func | $func $a
+  done)
+}
+
+mean() {
+  tee >(wc -l > count) | fold sum | xargs echo "scale=5;(1/" $(cat count) ") * " | bc
+}
+
+(echo 3; echo 1; echo 4) | mean