From: Esposito Francesco <address@hidden>
To: Hillel Rosensweig <address@hidden>; "address@hidden" <address@hidden>
Cc:
Sent: Friday, February 25, 2011 12:52 PM
Subject: Re: filter.oct
I need to implement a filter function in C language with the SAME behaviour of the Matlab one.
I solved the problem.....
I get the formula from
http://www.mathworks.com/help/techdoc/ref/filter.html
of the "direct form II transposed" and i have added the effect of zi because my function call is like:
y=filter(b,a,x,zi);
where a and b are filter coefficient vectors
x is the input
and zi is the initial conditions
it seems to work fine.......
thanks everybody
On Fri, 25 Feb 2011 02:03:51 -0800 (PST)
Hillel Rosensweig <
address@hidden> wrote:
>
>
> HI, I'm long time user, first time writer,
>
> I've been trying to implement the Octave 'filtert.oct' function in C. i built a function - 'filter.c' based on the information given in the online octave manual.
> the problem is that my code is relatively slow.
>
> I noticed that the actual function is a 'built-in' octave function and as such I
cannot review the code it runs. As i understand it, the
> octave code is optimized beyond the naive algorithm and I was wondering whether the algorithm used is available for reading anywhere .
>
> in other words - how did you guys do it?
>
> thanks
>
> Hillel
>
>
>