Hi , i need help to write a user defined functions to find positive
maximum and positive minimum
and also negative maximum and negative minimum from a range consists
of both positive and
negative numbers.

ex: 15,18,12,7,3,-9,-13,-23
In my requirement the result should come as
Positive Max: 18
Positive Minimum :3
Negative Maximum: -9
Negative minimum : -23

Thanks in advance for your response.