Symbolic link to application - working directory

Lets say i have a bash script in a folder called

, which reads data from files in a subfolder named

.
The paths in the script to the files are all relative to this "Programming" folder.

"test" > ./data/test.txt

.
So the working directory should always be the "Programming" folder.
When the script passes all tests, it is finished and i thought i could easily copy the whole content of the "Programming" folder to a subfolder in

/opt

, lets say

/opt/myapplication

and then make a symbolic link in the

/usr/bin

folder called

, which links to the script in

/opt/myapplication/bash_script

to make it reachable in the environment. But the problem is, if i now call myapplication from anywhere the working directory is

$PWD= #actual shell directory at script start
$0=/usr/bin/myapplication
${BASH_SOURCE}=/usr/bin/myapplication

and my application fails. I thought the symbolic link will change the working directory, to where the file is located. What is the common practice in Unix to set the working directory always, to where the executed file is located, to use relative paths ??