=MAX( MAX( sum(A1:A5), sum(A7:A11) ) - sum(A13:A17), 0)
Jimmy
2008-11-25 00:45:44
Thanks. It seems to work mauch faster than may array.
2008-11-25 03:35:57
This should have been an edit to your orignial post, or a comment to Jimmy's answer
Draemon
2008-12-02 04:34:52
A:
You may want to look into the VB Macro editor. In the Tools Menu, go to Macros and select Visual basic Editor. This gives a whole programming environment where you can write your own function.
VB is a simple programming language and google has all the guidebooks you need.
There, you can write a function like MySum() and have it do whatever math you really need it to, in a clear way written by yourself.
I pulled this off google, and it looks like a good guide to setting this all up. http://office.microsoft.com/en-us/excel/HA011117011033.aspx
Karl
2008-11-25 04:51:09
A:
This seems to work:
{=SUM(IF(A1:A5>A7:A11,A1:A5-A13:A17,A7:A11-A13:A17))}
EDIT - doesn't handle cases where subtraction ends up negative
This works - but is it more efficient???
{=SUM(IF(IF(A1:A5>A7:A11,A1:A5,A7:A11)>A13:A17,IF(A1:A5>A7:A11,A1:A5,A7:A11)-A13:A17,0))}
DJ
2008-11-25 18:54:09
A:
What about this?
=MAX(SUM(IF(A1:A5>A7:A11, A1:A5, A7:A11))-SUM(A13:A17), 0)
Edit:
Woops - Missed the throwing out negatives part. What about this? Not sure it it's faster...
=SUM((IF(A1:A5>A7:A11,IF(A1:A5>A13:A17,A1:A5,A13:A17),IF(A7:A11>A13:A17,A7:A11,A13:A17))-A13:A17))
Edit 2:
How does this perform for you?
=SUM((((A1:A5>A13:A17)+(A7:A11>A13:A17))>0)*(IF(A1:A5>A7:A11,A1:A5,A7:A11)-A13:A17))
Nathaniel Reinhart
2008-11-27 00:02:09
+1
A:
A more calculation-efficient (and especially re-calculation efficient) way is to use helper columns instead of array formulae:
C1: =MAX(A1,A7)-A13
D1: =IF(C1>0,C1,0)
copy both these down 5 rows
E1: =SUM(D1:D5)
Excel will then only recalculate the formulae dependent on any changed value, rather than having to calculate all the virtual columns implied by the array formula every time any single number changes. And its doing less calculations even if you change all the numbers.