?
Solved

Fourier Analysis Excel 2007 array size error

Posted on 2011-03-10
11
Medium Priority
?
1,172 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
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 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 26

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
Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

 
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 26

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 26

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 26

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

VIDEO: THE CONCERTO CLOUD FOR HEALTHCARE

Modern healthcare requires a modern cloud. View this brief video to understand how the Concerto Cloud for Healthcare can help your organization.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This article describes a serious pitfall that can happen when deleting shapes using VBA.
This article describes how you can use Custom Document Properties to store settings and other information in your workbook so that they will be available the next time you open the workbook.
This Micro Tutorial demonstrates how to create Excel charts: column, area, line, bar, and scatter charts. Formatting tips are provided as well.
Excel styles will make formatting consistent and let you apply and change formatting faster. In this tutorial, you'll learn how to use Excel's built-in styles, how to modify styles, and how to create your own. You'll also learn how to use your custo…

764 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