Newbie question



Hello all,

 

I have a text file with a single column of 2048 numerical values, which
are measurements made at a 1 second interval.

 

I wish to use the FFT function to generate and display a frequency
spectrum of the data.

 

I can happily use "read_array" to post the numbers from my file in to a
2048  element array

 

However, using the command fft( ) on the 2048 element array results in
maxima producing an outputg40613 with the numeric part incrementing by
one, each execution.

 

Can anyone assist by dropping me a few lines of code to allow me to view
a frequency spectrum of my data array?

 

Hopeful thanks in advance,

 

John

 

 

(%i29) 

array(datalist,float,2048-1); 


 

(%i30) 

(read_array("C:/TSS.txt",datalist)); 


 

(%i18) 

load(fft); 


 

(%i39) 

fft(datalist); 


 

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