Forum Discussion
Iterative calculations return #NUM
Hi!
I am running a T420 (old) lenovo thinkpad laptop with windows 10 pro and excel - office 365.
When trying to use iterative calculation, excel only returns #NUM, even for simple calculations.
For example :
A1=A2^3(should be 😎😎
A2=10-A1(should be 2)
Iterative calculation is enabled and I tried different number of iterations and precision, but it never works.
Here are different fixes I tried to no avail:
Tried installing an older version of excel (2010) but had same problem
Tried repairing office through office app
Does anyone have any clue what could be happening?
Thanks in advance
Even my engineer programming teacher couldn't solve this one... HELP!!
davididofff .... In English, the problem is: ``find a number such that 10 minus the number cubed is the number``.
Try the following system of formulas:
A1: =IF(A3="",0,IF(A2=0,A1,A1+1))
A2: =10-A1^3-A1
A3: empty, initially
Alternatively:
A1: =IF(A3="",0,IF(A2=A1,A1,A1+1))
A2: =10-A1^3
Enter anything into A3 to start the iterative calculation. Delete the value in A3 to start over.
For grins, change 10 in A2 to 2, 30, 68, 130, etc.
Remember to delete the value in A3 before changing A2. Otherwise, we get the wrong result because A1 does not start at zero.
7 Replies
davididofff .... In English, the problem is: ``find a number such that 10 minus the number cubed is the number``.
Try the following system of formulas:
A1: =IF(A3="",0,IF(A2=0,A1,A1+1))
A2: =10-A1^3-A1
A3: empty, initially
Alternatively:
A1: =IF(A3="",0,IF(A2=A1,A1,A1+1))
A2: =10-A1^3
Enter anything into A3 to start the iterative calculation. Delete the value in A3 to start over.
For grins, change 10 in A2 to 2, 30, 68, 130, etc.
Remember to delete the value in A3 before changing A2. Otherwise, we get the wrong result because A1 does not start at zero.
- Thanks! This works for me seems a bit complicated for such calculations but at least it works. Cheers!
davididofff Other than a cool thing to try, what is the purpose of such a nonsense calculation?
- Iterative calculations have many uses. As of doing it in excel, I agree and would prefer other apps. In this case, it is for an exam.
That's not the solver (which exists as add-in for Excel), that's literally iterations. Excel starts from blank cells which is zero. If only one iteration
A1=0^3=0
A2=10-0=10
Next (2nd iteration)
A1=10^3=1000
A2=10-1000=-990
Next (3rd iteration)
A1=-990^3=-970299000
A2=10-(-970299000) = 970299010
If you keep default 100 iteration very fast you'll be out of limits for number, thus #NUM! error. I guess less than 10 iterations enough.
