add histop function to show most used commands from history

plugins/history/history.plugin.zsh

@@ -6,3 +6,37 @@ function hs
 }
 
 alias hsi='hs -i'
+
+# show the most used commands from history
+function histop() {
+	local FNAME='histop'
+	local n=10
+	if [[ $# -ne 0 ]]; then
+		case $1 in
+			-h|--help)
+				echo "Usage: $FNAME -n <num>"
+				echo "num: print num lines of most used command"
+				return 0
+				;;
+			-n)
+				if [ $# -eq 2 -a $2 -ge 1 -a $2 -le $HISTSIZE ]; then
+					n=$2
+					shift
+				else
+					echo "option -n needs an number"
+					return 1
+				fi
+				;;
+			*)
+				echo "$FNAME: Unknown option: $1"
+				$FNAME --help
+				return 1
+				;;
+		esac
+		shift
+	fi
+	print "Number\tTimes\tFrequency\tCommand"
+	history 1 | awk -v n=$n '{ cmds[$2]++; } END { i = 1; for (cmd in cmds) {
+		if (i++ <= n) printf("%-8d%8.2f%%\t%-16s\n", cmds[cmd],
+			(100*cmds[cmd])/NR, cmd); else break; }}' | sort -nr | nl
+}