for myi in 0 1 2 ; do
eval mvar$myi=$myi
done
myi=1
eval newvar="\$mvar$myi"
echo $newvar
eval newvar="\$mvar0"
echo $newvar
-----------------------------------------------------------
eval mvar0=0
eval mvar1=2
eval mvar2=3
eval newvar="\$mvar0"
echo $newvar
eval newvar="\$mvar2"
echo $newvar