Re: lpc and hilbert functions

[Paul Kienzle]

Jim,

The sumskipnan problem seems to have been corrected in
octave-forge  CVS.  i don't know when off hand, but I don't
see it in the code now.  You can just comment out the
reference to the flag in the file.

Re: hilbert, the transform of a real signal x is placed in the
imaginary part of a complex signal z, leaving the real part
untouched.  Use imag(hilbert(z)) to retrieve it.
E.g.,

         t=linspace(0,10,256);
         z = hilbert(sin(2*pi*0.5*t));
         grid on; plot(t,real(z),';real;',t,imag(z),';imag;');

Paul Kienzle
address@hidden


On May 21, 2004, at 11:13 AM, Jim Brennan wrote:

> Newbie 
>  
> Iam getting an error with lpc :
>  
> error: `flag_implicit_skip_nan' undefined near line 119 column 5
> error: if: error evaluating conditional expression
> error: evaluating if command near line 119, column 2
> error: evaluating if command near line 62, column 1
> error: called from `sumskipnan' in file 
> `/opt/octave/share/octave/2.1.50/site/m/octave-forge/NaN/sumskipnan.m'
> error: called from `lattice' in file 
> `/opt/octave/share/octave/2.1.50/site/m/octave-forge/tsa/lattice.m'
> error: called from `lpc' in file 
> `/opt/octave/share/octave/2.1.50/site/m/octave-forge/tsa/lpc.m'
>  
> Any ideas what I am doing wrong? Doesn't seem to matter what the input 
> is.
>
>
>
> Also with the hilbert function shouldn't this return a vector of 
> cos(x) values if a vector of sin(x) values is input. Assume the x 
> values are evenly spaced 0 to 2pi. Not sure I understand the output of 
> this function. Any further explanation would be appreciated.
>  
> Jim



-------------------------------------------------------------
Octave is freely available under the terms of the GNU GPL.

Octave's home on the web:  http://www.octave.org
How to fund new projects:  http://www.octave.org/funding.html
Subscription information:  http://www.octave.org/archive.html
-------------------------------------------------------------