Re: Help-octave Digest, Vol 30, Issue 65

[Jaroslav Hajek]

On Thu, Sep 25, 2008 at 7:19 AM, Russell jarvis
<address@hidden> wrote:
> I wonder if any can tell me how to declare an empty multidimensional
> array or matrix.
>
> I declare a blank 1 dimensional array:
>
> array1 = [];
>

No, Octave does not know 1 dimensional arrays. This creates an empty 0x0 matrix.


> but I want to do something like:
>
> array2=[][];
>

You can reshape [] to any empty shape you want.


> Thanks for any help.
>
> Russell.
>
> On Thu, Sep 25, 2008 at 3:03 AM,  <address@hidden> wrote:
>> Send Help-octave mailing list submissions to
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>> Today's Topics:
>>
>>   1. Re: Fwd: Gaussian fit of a peak (LUK ShunTim)
>>   2. Re: Gaussian fit of a peak (Rob Mahurin)
>>   3. Re: strange regexp behavior (John W. Eaton)
>>   4. Returned value from function as a global variable (LUK ShunTim)
>>
>>
>> ----------------------------------------------------------------------
>>
>> Message: 1
>> Date: Wed, 24 Sep 2008 18:08:21 +0800
>> From: LUK ShunTim <address@hidden>
>> Subject: Re: Fwd: Gaussian fit of a peak
>> To: Andrea Cimatoribus <address@hidden>
>> Cc: address@hidden
>> Message-ID: <address@hidden>
>> Content-Type: text/plain; charset=UTF-8
>>
>> Andrea Cimatoribus wrote:
>>> Here is what Octave says:
>>>
>>> octave-3.0.0:3> pkg install miscellaneous-1.0.7.tar.gz
>>> configure: WARNING: no mkoctfile found on path
>>
>> You need to install the octave3.0-headers debian/ubuntu package (which
>> provides mkoctfile etc) to install most octave-forge packages.
>>
>> Regards,
>> ST
>> --
>>
>>
>> ------------------------------
>>
>> Message: 2
>> Date: Wed, 24 Sep 2008 11:26:23 -0400
>> From: Rob Mahurin <address@hidden>
>> Subject: Re: Gaussian fit of a peak
>> To: "Andrea Cimatoribus" <address@hidden>
>> Cc: address@hidden
>> Message-ID: <address@hidden>
>> Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed
>>
>> On Sep 24, 2008, at 4:04 AM, Andrea Cimatoribus wrote:
>>> Unfortunately, I am not sure I will be able to keep "central" area
>>> only, since I am fitting something that resembles a phonon spectra.
>>> In fact, I have multiple peakes to the left and right with respect
>>> to the "zero", but fitting everything with a gaussian balanced to
>>> the zero energy pretty well. I need to do this in order to sum
>>> spectra together. I will let you know if and how I solve this
>>> problem if it is of any intereset.
>>> AC
>>
>> The leasqr wrapper I mentioned can handle multiple overlapping
>> Gaussians.  You might wonder, for instance, whether a fit to two
>> unresolved peaks gives a smaller chi-squared per degree of freedom
>> than a fit to a single peak.  This is what the "demo" does for a
>> dodgy problem with two exponentials.  (Though you have to find the
>> chi2 yourself, sum( ((y-f5)./errscale).^2 ), after the demo runs,
>> because I wasn't thinking of this when I wrote it).
>>
>> If you have some constant background you'll have to subtract it by
>> hand for now.
>>
>> code, again, at
>>        http://sns.phys.utk.edu/~mahurin/octave/
>>
>> Cheers,
>> Rob
>>
>> --
>> Rob Mahurin
>> Dept. of Physics & Astronomy
>> University of Tennessee         phone: 865 207 2594
>> Knoxville, TN 37996             email: address@hidden
>>
>>
>>
>> ------------------------------
>>
>> Message: 3
>> Date: Wed, 24 Sep 2008 11:40:21 -0400
>> From: "John W. Eaton" <address@hidden>
>> Subject: Re: strange regexp behavior
>> To: David Bateman <address@hidden>
>> Cc: address@hidden, "G.." <address@hidden>
>> Message-ID: <address@hidden>
>> Content-Type: text/plain; charset=us-ascii
>>
>> On 23-Sep-2008, David Bateman wrote:
>>
>> | Ok, then what about the attached changeset for 3.1.51+ based on your
>> | patch that
>> |
>> | * Adds a call to OCTAVE_QUIT
>> | * Adds the loop counter to terminate for truly infinitely recursive 
>> patterns
>> | * Adds a test based on the previously failing code.
>> |
>> | I compiled and tested this sucessfully with 3.1.51+ and suppose it will
>> | work for 3.0.2+ as well.
>>
>> I applied it.
>>
>> Thanks,
>>
>> jwe
>>
>>
>> ------------------------------
>>
>> Message: 4
>> Date: Thu, 25 Sep 2008 00:20:13 +0800
>> From: LUK ShunTim <address@hidden>
>> Subject: Returned value from function as a global variable
>> To: address@hidden
>> Message-ID: <address@hidden>
>> Content-Type: text/plain; charset=ISO-8859-1
>>
>> Hi,
>>
>> I had some matlab code which uses global variables to allow common
>> access to returned values from functions. It appears that octave doesn't
>> allow such behaviour. Here's a short function which produces an error in
>> octave.
>>
>> function [v]=t_global_f(x)
>>    global v;
>>    v = sin(x);
>> endfunction
>>
>> octave:1> x=0:0.1:pi;
>> octave:2> v=t_global_f(x);
>> error: can't make function parameter `v' global
>> error: evaluating global command near line 6, column 1
>> error: called from `t_global_f' in file
>> `/home/0/00work/octave/00snippets/t_global_f.m'
>> error: evaluating assignment expression near line 2, column 2
>>
>> Is there any plan to implement the same behaviour in octave?
>>
>> Regards,
>> ST
>> --
>>
>>
>>
>> ------------------------------
>>
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>>
>> End of Help-octave Digest, Vol 30, Issue 65
>> *******************************************
>>
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-- 
RNDr. Jaroslav Hajek
computing expert
Aeronautical Research and Test Institute (VZLU)
Prague, Czech Republic
url: www.highegg.matfyz.cz