The Math Forum

Search All of the Math Forum:

Views expressed in these public forums are not endorsed by NCTM or The Math Forum.

Math Forum » Discussions » Software » comp.soft-sys.matlab

Notice: We are no longer accepting new posts, but the forums will continue to be readable.

Topic: DFT vs DWT on raw data
Replies: 1   Last Post: May 2, 2013 6:02 PM

Advanced Search

Back to Topic List Back to Topic List Jump to Tree View Jump to Tree View   Messages: [ Previous | Next ]
Derek Goring

Posts: 3,922
Registered: 12/7/04
Re: DFT vs DWT on raw data
Posted: May 2, 2013 6:02 PM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

On Friday, May 3, 2013 8:17:09 AM UTC+12, Jurgens J J Cornelius wrote:
> Hi
> Hope somebody can help! I have an Xcel spreadsheet with time in milliseconds in the first column and rms voltage in the second recorded during disturbances. I would like to apply the DFT as well as the DWT on this data to compare the results and decide which tool to use for further data manipulation from time to freq. domain. Has anyone done this exercise and how would I go about setting out the data into the DFT?
> Thank you very much.

If the data are equispaced, you don't need the time, just the interval between them.
So, you read the data in using xlsread, extracting just the 2nd column.
help fft
to get the DFT, and:
help dwt
to get the DWT.

You should search this newsgroup to find out how to calculate the frequencies for the DFT and the timescales for the DWT.

Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© The Math Forum at NCTM 1994-2018. All Rights Reserved.