Combining multiple nested IFs with an OR condition

[dmitrevski]

I need help with joining two sets of multiple nested IF formulas. I believe I need to use the OR condition but can't get this to work.
I'm essentially trying to say : IF D12 > D21 , do this... OR IF D12 < D21 do this... I can evaluate the each nested IF before and after the OR successfully.
It's when I try to combine the two pieces that I run into trouble.
Excel is not my first language. I'm a SQL developer, so getting the syntax correctly is proving difficult for me.

These are my two sets of nested IFs that work on their own. How do I add the OR condition in, to create one large formula?
=IF(D12>D21,0,
IF(AND(AND(D15>0,D12<=D21),D12>=D22),(D22-D12)*-0.5,
IF(AND(AND(D15<0,D12<=D21),D12>=D22),(D22-D12)*0.5,
IF(AND(AND(D15>0,D12<=D22),D12>=D23),(D22-D12)*-0.5,
IF(AND(AND(D15<0,D12<=D22),D12>=D23),(D22-D12)*0.5
)))))


=IF(D12<D21,0,
IF(AND(AND(D15>0,D12<=D21),D12>=D22),(D12-D22)*-0.5,
IF(AND(AND(D15<0,D12<=D21),D12>=D22),(D12-D22)*0.5,
IF(AND(AND(D15>0,D12<=D22),D12>=D23),(D12-D22)*-0.5,
IF(AND(AND(D15<0,D12<=D22),D12>=D23),(D12-D22)*0.5
)))))

Thank you!!!

 

[DanteAmor]

How about:

=IF(D12>D21,
IF(AND(AND(D15>0,D12<=D21),D12>=D22),(D12-D22)*-0.5,
IF(AND(AND(D15<0,D12<=D21),D12>=D22),(D12-D22)*0.5,
IF(AND(AND(D15>0,D12<=D22),D12>=D23),(D12-D22)*-0.5,
IF(AND(AND(D15<0,D12<=D22),D12>=D23),(D12-D22)*0.5)))),
IF(AND(AND(D15>0,D12<=D21),D12>=D22),(D22-D12)*-0.5,
IF(AND(AND(D15<0,D12<=D21),D12>=D22),(D22-D12)*0.5,
IF(AND(AND(D15>0,D12<=D22),D12>=D23),(D22-D12)*-0.5,
IF(AND(AND(D15<0,D12<=D22),D12>=D23),(D22-D12)*0.5
)))))

 

[dmitrevski]

Ah, thank you Dante! I see what you did there, with replacing the 'zero' argument with the one of the OR conditions. I'm going to continue testing scenarios, but it looks to be working for me. Thank you again!

 

[DanteAmor]

I'm glad to help you. Thanks for the feedback.