1 files changed, 62 insertions, 0 deletions
diff --git a/mean_avg.awk b/mean_avg.awk
new file mode 100644
index 0000000..799f96c
--- /dev/null
+++ b/mean_avg.awk
@@ -0,0 +1,62 @@
+#!/usr/bin/awk
+
+### mean_avg.awk
+# average columns of numerical data
+
+BEGIN {
+    sign = "[+-]?"
+    decimal = "[0-9]+[.]?[0-9]*"
+    fraction = "[.][0-9]*"
+    exponent = "([Ee]" sign "[0-9]+)?"
+    number = "^" sign "(" decimal "|" fraction ")" exponent "$"
+}
+
+NR == 1 {
+    header_nf = NF
+    for (n=1; n<=NF; n++) {
+        if ($n !~ number)
+            header[n] = $n
+    }
+}
+
+NF != 0 {
+    if (NF > max_nf)
+        max_nf = NF
+    for (n=1; n <= NF; n++) {
+        if ($n !~ number) {
+            continue
+        }
+        if ($n ~ number) {
+            count[n] += 1
+            sum[n] += $n
+            sum2[n] += $n*$n
+            mean[n] = sum[n]/count[n]
+            delta[n] = $n - mean[n]
+            delta2[n] = delta[n]*delta[n]
+            sum_delta[n] += delta[n]
+            sum_delta2[n] += delta2[n]
+            if ((count[n] - 1) != 0)
+                var[n] = sum_delta2[n]/(count[n] - 1)
+            else
+                var[n] = 0
+        }
+    }
+}
+
+END {
+    printf("\n")
+    printf("%-6s\t%-6s %-6s %-6s\n", "col", "mean", "std_err", "count")
+    for (n=1; n<=max_nf; n++) {
+        if (header[n])
+            printf("%-6s\t", header[n])
+        else
+            printf("%-6g\t", n)
+        if (count[n]) {
+            printf("%-6g ±%-6g %-6g\n",
+                mean[n], 1.96*sqrt(var[n]/count[n]), count[n])
+        }
+        else
+            printf("%2s %2s %2s\n", " ", " ", " ")
+    }
+}
+