Improve company productivity with a Business Account.Sign Up

x
?
Solved

Fourier Analysis Excel 2007 array size error

Posted on 2011-03-10
11
Medium Priority
?
1,300 Views
Last Modified: 2012-05-11
This is Excel 2007.  I did a Fourier Analysis over an array of 512 real numbers yielding an array of 512 complex numbers.
Then I tried to do a 2nd array of the same size.
The function errors out saying that the arrays need to be sized a power of 2.  512 is a power of two.
The exact row numbers are x3:x514.
514 -3 +1 is 512 rows of course......
Please help!
0
Comment
Question by:Fred Marshall
  • 7
  • 4
11 Comments
 
LVL 30

Expert Comment

by:SiddharthRout
ID: 35104566
512 is a valid size as it is a power of two. Can I see the code that you are using?

Sid
0
 
LVL 30

Expert Comment

by:SiddharthRout
ID: 35104803
Also I want to see how are you populating the 2nd array? You might want to try this to check if it is actually a 512 sized array?

'~~> Replace MyArray with the name of the array
Debug.Print Ubound(MyArray)

Open in new window


Sid
0
 
LVL 27

Author Comment

by:Fred Marshall
ID: 35104963
I didn't do anything re: arrays really.

I just used the Fourier Analysis Input Range and Output Range pretty much like I said originally.

$E$3:$E$514
$H$3:$H$514

Just for the heck of it I did this:
I ran it over 256 cells and got the results.
Then I repeated those cells to get 256
Then I did an Inverse over the 512 and it worked fine.

The Inverse values are purely real as expected.
But, when I try to format them down to 1 or 2 decimal places they don't change at all!

I don't know how to do the Debug.Print Unbound thing......
0
Get your problem seen by more experts

Be seen. Boost your question’s priority for more expert views and faster solutions

 
LVL 30

Expert Comment

by:SiddharthRout
ID: 35104972
I used the same range and didn't get an error?

Sid
0
 
LVL 30

Expert Comment

by:SiddharthRout
ID: 35104975
BTW when I say Error I am referring to your main array size error.

Sid
0
 
LVL 30

Accepted Solution

by:
SiddharthRout earned 2000 total points
ID: 35105235
>>>The Inverse values are purely real as expected.
But, when I try to format them down to 1 or 2 decimal places they don't change at all!

I see what you mean...

That is because the numbers are stored as text. See snapshot 1. If you convert them to number then you will get the desired results. (See snapshot 2)

Sid


Untitled.jpg
Untitled2.jpg
0
 
LVL 27

Author Comment

by:Fred Marshall
ID: 35105948
Now it says that all the complex numbers have to have the same suffix either "i" or "j" but they were generated by Excel!!

I don't get the error you show to work on...
0
 
LVL 30

Expert Comment

by:SiddharthRout
ID: 35105960
Can you upload your file?

Sid
0
 
LVL 27

Author Comment

by:Fred Marshall
ID: 35106019
I did find an error.  One of the input arrays had some blank cells in it.  Seems to be working better now.
0
 
LVL 30

Expert Comment

by:SiddharthRout
ID: 35106120
Gr8 :)

Sid
0
 
LVL 27

Author Closing Comment

by:Fred Marshall
ID: 35108587
I likely would not have noticed this little pastel icon/button nor known what to do with it.  It helped quite a bit in fixing this problem!
0

Featured Post

Free Tool: Subnet Calculator

The subnet calculator helps you design networks by taking an IP address and network mask and returning information such as network, broadcast address, and host range.

One of a set of tools we're offering as a way of saying thank you for being a part of the community.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

Join & Write a Comment

This article describes how to use a set of graphical playing cards to create a Draw Poker game in Excel or VB6.
Windows Explorer let you handle zip folders nearly as any other folder: Copy, move, change, and delete, etc. In VBA you can also handle normal files and folders, but zip folders takes a little more - and that you'll find here.
This Micro Tutorial will demonstrate how to use longer labels with horizontal bar charts instead of the vertical column chart.
Many functions in Excel can make decisions. The most simple of these is the IF function: it returns a value depending on whether a condition you describe is true or false. Once you get the hang of using the IF function, you will find it easier to us…

589 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question