[Help-bash] export

[Val Krem]

Hi all,

I am trying to export  a variable from a shell script. The script is working 
well if  I run my  script without an argument ( $#=0).  I am inter4ested in   
to export the variable if the $# -ge 1  but did not work for me.   Below is my 
my "broken" script.


######################### mtest.sh ###########################################

#!/bin/bash

ftmp=$(date  +%m%Y);export ftmp       # ftmp= 022017
mp=/val/data/

flag=$1; export flag
nwork=$2; export nwork
narg=$#; export narg


if [ ${narg}  -eq 0 ]; then
                if [ ! -d "${mp}"/"${ftmp}" ]; then
                     mkdir "${mp}"/"${ftmp}"   
    fi
                  mp2="${mp}"/"${ftmp}"; export mp2                  

 elif   [ "${narg}" -ge 1 ]  && [ "${flag}" !=  "-t" ]; then
      echo "illegal option!"
    exit 1
  else

    if [ "${narg}" -eq 2 ]  &&  [ "${flag}" == "-t" ]; then
     if [ ! -d ${mp}/${ftmp}/${nwork} ]; then
        mkdir ${mp}/${ftmp}/${nwork}
     fi
        mp2=${mp}/${ftmp}/${nwork} ; export mp2
   fi
fi
echo "end of testing"
##############################################################


1. if I execute   ./mtest.sh
  I am getting  :    mp2= /val/data/022017

2. if I execute with  ./mtest  -t  tdat
 still I am getting    mp2= /val/data/022017

 but I want to get    mp2= /val/data/tdat/022017.

I would appreciate if you help me out here

thank you in advance