I am stumped! 1

[porf]

I am stumped on what seems like a fairly simple calculation using a spreadsheet. I have four vertical user boxes for input of variables. Call them C21, C22, C23 and C24. In C25 I have an equation that uses information from the previous four cells to calculate an answer for C25. Then I have another equation in cell C26 which uses the results from C25. Well the spreadsheet provides an accurate answer the first time around. But then if I go back and input new information in cell C23, which is used in the first equation (C25), C26 for the second equation just lays there without computing a result. Could there be a simple solution for this anomaly? Or is it that I am flat out doing something wrong. Appreciate your feedback.

 

[yakpol]

Set calculations to auto mode. Open Tools-Options-Calculations and check mark Auto. Or press F9 to see the updated results.

 

[porf]

I tried both of your sugestions. It was already in AUTO and F9 did not recalculate. Here is what I have:
C23 21
C24 2
C25 4160
C26 0.015

C29 =((C23*1000000)/C25*1.732*100)/C24

C32 =C25*C29*1.732*0.000001*0.707*0.707

My initial question had hypothetical cell numbers. SO specifically, I am not using cells C27,C28,C30 and C31. Thus when I input a value into C25, C32 doe not re-calculate. Could there be other features in the options menu I should check? I really appreciate your assistance as a lot of people are counting on realiable results.

 

[yakpol]

Porf,
Sometimes Excel does strange things... It may be worth rebooting computer or starting new spreadsheet in the case of this kind of unexpected error.

 

[Briansch]

porf, I think I see your problem.

This is your value for C29:

=((C23*1000000)/C25*1.732*100)/C24

and C32 is C29 multiplied by C25 times some constant. You can see, though, that the C25 value will cancel (one in numerator and one in demominator) so the value of C32 will not change if C23 and C24 do not change.

Hope this helps.

 

[porf]

Great going guys. I definitely see the problem now. I really appreciate your quick response.

 

[porf]

Thank you all for your responses. A colleague of mine just pointed out to me that there is nothing wrong with the original set-up. Equations are doing what they are supposed to do. In other words, from the engineering standpoint, results are what is expected and excel formulas reflect this as well. It was a matter of recognizing the intent of the equations and recognizing this as well in the excel spreadsheet results.