Apparently you haven't read the headline, it says "missing functions"!
Therefore, there is currently no gaussfir in the signal package, but
it's on the wishlist. That doesn't mean anyone will implement it in the
near future. You could be the one, if you look up the math somewhere.
> Also, what’s the recommended download link for Octave for Windows 7
> 64bit? (I may have seen more than one) and have you experienced any issue
> on Windows?
I haven't used Windows for some time now. A few years ago the best way
to get octave was by installing cygwin. That may have changed now.
> Can both be called from a C compiler? (Like the free MS Visual C++
> Express)
It is relatively easy to write functions in C which are called by
octave. There is a script, mkoctfile, which calls the compiler on your
C++ file and transforms it into a loadable function. I have never done
the other way round, however it's possible by using feval() to call out
to the interpreter.
> Can both allow real-time processing of the PC’s external analog
> input-output? (i.e. without using any input/output file)
Never tried. I know that Matlab can do it, but typically, it is used as
a prototyping system and for hands-on calculation, rarely for production
work. I would only consider this if there is a complicated algorithm too
heavy to be reimplemented in a compiled language. A compiled language
gives a performance boost in many cases.
Christian
Reply by Eric Jacobsen●June 25, 20132013-06-25
On Tue, 25 Jun 2013 12:43:25 -0500, "Ro_ny" <95309@dsprelated> wrote:
>
>>>Is it possible that the said function appears in Octave?
>>>http://wiki.octave.org/Signal_package
>>
>>linspace is in Octave, if that's what you're asking about. You didn't
>>specify and didn't quote what you're responding to, so it's hard to
>>know what you're inquiring about.
>
>This question refers to the gaussfir(bt,n,o) as the word gaussfir seems to
>appear in the above link.
Yes, gaussfir appears in the link which you provided, which is a link
clearly identified as a listing of functions which ARE NOT part of
Octave.
I'm incredulous that you posted the link to the answer of the question
that you were asking as part of the question while you were asking it.
>Thank you both.
>
>_____________________________
>Posted through www.DSPRelated.com
>>Is it possible that the said function appears in Octave?
>>http://wiki.octave.org/Signal_package
>
>linspace is in Octave, if that's what you're asking about. You didn't
>specify and didn't quote what you're responding to, so it's hard to
>know what you're inquiring about.
This question refers to the gaussfir(bt,n,o) as the word gaussfir seems to
appear in the above link.
Thank you both.
_____________________________
Posted through www.DSPRelated.com
Reply by Tim Wescott●June 25, 20132013-06-25
On Tue, 25 Jun 2013 09:26:27 -0500, Ro_ny wrote:
> Hi Christian,
>
> Is it possible that the said function appears in Octave?
> http://wiki.octave.org/Signal_package
>
> Also, what’s the recommended download link for Octave for Windows 7
> 64bit? (I may have seen more than one) and have you experienced any
> issue on Windows?
>
> Questions for people regarding both the Octave and Scilab programs:
>
> Can both be installed and work on PC (Windows) without internet
> connection?
A PC without Internet? What's that?
Seriously -- Scilab installs from an exe; you'd need to burn it onto a CD
or put it on a thumb drive, but from there you could install it
wherever. I can't speak directly for Octave, but I think the answer is
yes.
> Can both be called from a C compiler?
Scilab is reputed to have that capability. I've gone the other way
(under Linux) and called routines written in C from Scilab.
> (Like the free MS Visual C++ Express)
The last time I looked Scilab for Windows was compiled under Visual C++,
so of the free alternatives that would be your best bet.
>
> Can both allow real-time processing of the PC’s external analog
> input-output? (i.e. without using any input/output file)
Theoretically Scilab can, but I've never tried it. Given that you can
call C functions there's a chance that you could make this happen
yourself, if you were savvy enough.
--
Tim Wescott
Control system and signal processing consulting
www.wescottdesign.com
Reply by Eric Jacobsen●June 25, 20132013-06-25
On Tue, 25 Jun 2013 09:26:27 -0500, "Ro_ny" <95309@dsprelated> wrote:
linspace is in Octave, if that's what you're asking about. You didn't
specify and didn't quote what you're responding to, so it's hard to
know what you're inquiring about.
>Also, what’s the recommended download link for Octave for Windows 7
>64bit? (I may have seen more than one) and have you experienced any issue
>on Windows?
> Questions for people regarding both the Octave and Scilab programs:
>
>Can both be installed and work on PC (Windows) without internet
>connection?
Octave will run fine without an internet connection.
>Can both be called from a C compiler? (Like the free MS Visual C++
>Express)
That's difficult in Octave.
>Can both allow real-time processing of the PC’s external analog
>input-output? (i.e. without using any input/output file)
That's difficult in Octave. I've done real-time stuff with Octave
using a home-grown file transfer handshake. There may be better
ways, but at the time the schedule did not permit finding them.
>PS: About the Prokais book, is there a free online link for reading?
Hi Christian,
Is it possible that the said function appears in Octave?
http://wiki.octave.org/Signal_package
Also, what’s the recommended download link for Octave for Windows 7
64bit? (I may have seen more than one) and have you experienced any issue
on Windows?
Questions for people regarding both the Octave and Scilab programs:
Can both be installed and work on PC (Windows) without internet
connection?
Can both be called from a C compiler? (Like the free MS Visual C++
Express)
Can both allow real-time processing of the PC’s external analog
input-output? (i.e. without using any input/output file)
PS: About the Prokais book, is there a free online link for reading?
Thanks,
Rony J.
_____________________________
Posted through www.DSPRelated.com
Reply by Christian Gollwitzer●June 24, 20132013-06-24
Am 24.06.13 17:15, schrieb Ro_ny:
> Hi Christian, Thank you for the explanation. I also thank Tim for the
> example.
> If we get back to the simple 1D Gaussian filter, is anyone here able to
> revise Tim’s example (in Octave/Scilab) to include the 3 parameters? (As
> changeable constants)
For Gaussian filtering, there are not so many parameters one can change.
It's basically the width( sigma, stddev) and number of samples. If you
look at my example, the second line probably contains all parameters you
need to change:
x=linspace(-3*sigma, 3*sigma, 15)
The "3" indicates, how far the Gaussian extends, the 15 is the nuber of
samples, and the sigma is the bandwidth. There might be another
parameter involved, namely a non-integer shift.
Simply look up the math - somebody must have already computed sigma for
you from your parameters, and then it's trivial. Why do you insist on us
doing your homework? If you look up the formulae, I will convert it to
octave for (probably trivial).
Christian
Reply by Ro_ny●June 24, 20132013-06-24
Hi Christian, Thank you for the explanation. I also thank Tim for the
example.
A GSM modulation is for some indirect assessment and practically I’m
going for another thing (sorry for not sharing here a commercial secret in
front of 5 digit people).
If we get back to the simple 1D Gaussian filter, is anyone here able to
revise Tim’s example (in Octave/Scilab) to include the 3 parameters? (As
changeable constants)
Rony J.
_____________________________
Posted through www.DSPRelated.com
Reply by Christian Gollwitzer●June 24, 20132013-06-24
Hi Rony,
Am 23.06.13 23:08, schrieb Ro_ny:
>> I think you're misunderstanding the utility of these packages. They're
>> MATH packages. You're doing DSP.
>
> I think this forum is destined first of all for DSP?:)
>
> Secondly, Matlab seems to have a command of gaussfir(bt,n,o) - what’s the
> equivalent of Scilab (and also Octave if should be similar) for it?
When talking about Matlab, there are two things:
A) Matlab, the language - a programming language specialized on
vector/matrix math
B) Matlab, the system - an IDE and a huge library of canned solutions
for common problems
Octave faithfully copies only A) - it has no IDE and lacks many of the
advanced functions you can find in "Matlab". OTOH, Matlab, the system,
only works if you buy a number of so called "toolboxes" with it. The
basic price for "naked" Matlab is around 2000€, every single Toolbox
costs you another ~1000€. The function "gaussfir" that you mentioned
belongs to the "Signal processing toolbox". If you would buy only
"Matlab", you would still not have it! For doing DSP work, you might
also need the "Optimization Toolbox", otherwise you have no function for
nonlinear least squares fitting, and the "Image processing toolbox" if
you need standard image operations like 2D-covolution, morphology
operators and so on.
In octave, the very standard stuff IS there, like "leasqr" for
non-linear least squares and "bwmorph" for morphological operators, but
the complete set of canned solutions is not available.
If you need only A), you are probably better off with Octave - it's
free, and it gives you the standard stuff, too. If you need B), then you
have to bite the bullet and buy Matlab. Be prepared to spend 5-10k€
depending on your needs.
Now, Gaussian filtering does not seem to be a problem using only A) -
that's what Tim has shown you. If there is no black magic behind
gaussfir (I no nothing about GMSK), you don't need the fancy DSP
toolbox. Repeating Tim's lines in Octave looks like this:
Apfelkiste:~ chris$ octave
GNU Octave, version 3.0.3
Copyright (C) 2008 John W. Eaton and others.
This is free software; see the source code for copying conditions.
There is ABSOLUTELY NO WARRANTY; not even for MERCHANTIBILITY or
FITNESS FOR A PARTICULAR PURPOSE. For details, type `warranty'.
Octave was configured for "i386-apple-darwin8.9.1".
Additional information about Octave is available at http://www.octave.org.
Please contribute if you find this software useful.
For more information, visit http://www.octave.org/help-wanted.html
Report bugs to <bug@octave.org> (but first, please read
http://www.octave.org/bugs.html to learn how to write a helpful report).
For information about changes from previous versions, type `news'.
octave-3.0.3:1> sigma=1.0
sigma = 1
octave-3.0.3:2> x=linspace(-3*sigma, 3*sigma, 15)
x =
-3.00000 -2.57143 -2.14286 -1.71429 -1.28571 -0.85714 -0.42857
0.00000 0.42857 0.85714 1.28571 1.71429 2.14286 2.57143
3.00000
octave-3.0.3:3> g=exp(-x.^2/(2*sigma^2))
g =
0.011109 0.036658 0.100669 0.230066 0.437565 0.692569
0.912254 1.000000 0.912254 0.692569 0.437565 0.230066
0.100669 0.036658 0.011109
octave-3.0.3:4> g=g/sum(g)
g =
Columns 1 through 13:
0.0019016 0.0062751 0.0172326 0.0393829 0.0749026
0.1185545 0.1561603 0.1711807 0.1561603 0.1185545 0.0749026
0.0393829 0.0172326
Columns 14 and 15:
0.0062751 0.0019016
octave-3.0.3:5> plot(x,g,'*')
All those commands should run unaltered in Matlab.
Christian
Reply by Tim Wescott●June 23, 20132013-06-23
On Sun, 23 Jun 2013 16:08:29 -0500, Ro_ny wrote:
>>I think you're misunderstanding the utility of these packages. They're
>>MATH packages. You're doing DSP.
>
> I think this forum is destined first of all for DSP?:)
Yes. And we get a number of people who confuse memorizing the function
calls in the Matlab DSP toolbox with having a deep knowledge of DSP.
> Secondly, Matlab seems to have a command of gaussfir(bt,n,o) - what’s
> the equivalent of Scilab (and also Octave if should be similar) for it?
I dunno -- but the code that I gave you makes a Gaussian FIR. Try
loading Scilab and typing
"help Gaussian".
See what happens.
Really, if you can't understand how to do the math for yourself, then
you're going to have a steep uphill climb trying to do any real DSP work.
--
Tim Wescott
Wescott Design Services
http://www.wescottdesign.com