SetEnv_rub_mn2standalone.bash: added option to set a new pawian env...

SetEnv_rub_mn2standalone.bash: added option to set a new pawian env (removing/overwriting existing env) and removed usage of already sourced root (need to source same root version from compilation to avoid crashed, so now will allways source root specified in user var ROOT_DIR)

SetEnv_rub_mn2standalone.bash

+#### check for existing pawian environment
+NEWTOPDIR=$(realpath "${BASH_SOURCE[0]}")
+NEWTOPDIR="${NEWTOPDIR%/*}"
+if [[ -z "$TOP_DIR" ]]; then
+    TOP_DIR="${NEWTOPDIR}"
+else
+    echo "pawian env already set to ${TOP_DIR}"
+    read -p "setup new env to ${NEWTOPDIR}? (yY/nN): " choice
+    if [[ "$choice" == "y" ]] || [[ "$choice" == "Y" ]]; then
+        LD_LIBRARY_PATH=${LD_LIBRARY_PATH/${MINUIT2_STANDALONE}\/lib:${TOP_DIR}\/lib/}
+        LD_LIBRARY_PATH=${LD_LIBRARY_PATH/::/:}
+        if [[ "${LD_LIBRARY_PATH:0:1}" == ":" ]]; then
+            LD_LIBRARY_PATH=${LD_LIBRARY_PATH:1}
+        fi
+        PATH=${PATH/${TOP_DIR}\/bin/}
+        PATH=${PATH/::/:}
+        if [[ "${PATH: -1}" == ":" ]]; then
+            PATH=${PATH:0: -1}
+        fi
+        TOP_DIR="$NEWTOPDIR"
+    elif [[ "$choice" == "n" ]] || [[ "$choice" == "N" ]]; then
+        echo "NO, pawian env remains to $TOP_DIR"
+        return
+    else
+        echo "invalid input, exiting"
+        return
+    fi
+fi
+
 ############################
 #### user defined variables
 ############################
@@ -14,21 +43,8 @@ EVT_DIR="/data/duldul/bertram/EvtStore/"
 # set Jamfile for bjam/b2 (a symlink Jamroot -> $JAM_FILE will be created)
 JAM_FILE="Jamroot_rub_AL9_mn2standalone"
 
-#### check for existing pawian environment
-if [[ -z "$TOP_DIR" ]]; then
-    TOP_DIR=$(realpath "${BASH_SOURCE[0]}")
-    TOP_DIR="${TOP_DIR%/*}"
-else
-    echo "pawian environment already exists, aborting setup new env"
-    return
-fi
-
-#### setup root (if needed)
-if [[ -z "${ROOTSYS}" ]]; then
-    source ${ROOT_DIR}/bin/thisroot.sh
-else
-    echo "root ${ROOTSYS} already sourced"
-fi
+#### source root
+source ${ROOT_DIR}/bin/thisroot.sh
 
 #### prepend minuit2 and pawian libs to LD_LIBRARY_PATH
 LD_LIBRARY_PATH="${MINUIT2_STANDALONE}/lib:${TOP_DIR}/lib${LD_LIBRARY_PATH:+:${LD_LIBRARY_PATH}}"