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Re: Octave not finding updated edited files


From: Ben Abbott
Subject: Re: Octave not finding updated edited files
Date: Wed, 18 Mar 2009 11:14:35 -0400

On Wednesday, March 18, 2009, at 08:54AM, "Jim Maas" <address@hidden> wrote:

>
>Ben Abbott wrote:
>>
>> On Mar 18, 2009, at 5:52 PM, Jim Maas wrote:
>>
>>> --------------------------------------------------------------------------------------------------
>>>  
>>>
>>> function dqadt = mmjam(t,y)
>>> %-----------------------------------------------------------------------
>>> % Specify the ODE (dynamic Michaelis-Menten expression)
>>> % file mmjam.m called from mmjam0.m
>>> % Dr. Jim Maas
>>> % 18/03/09
>>> %-----------------------------------------------------------------------
>>> % Get rate constants from outside this function
>>>     global vmax km size qin
>>> % Work in a more comprehensible set of variables
>>>     qa  = y;
>>> % Subsidiary equations--------------------------------------------------
>>>     ca = qa / size;
>>>     qaout = vmax / ( 1 + ( km / ca));
>>> % Dynamic equations--------------------------------------------------
>>> %      dqadt(1) = qin - qaout; % dqa/dt
>>>     dqadt = qin - qaout; % dqa/dt
>>
>> Jim, I don't see where the input "t" is being used.
>>
>> It that an error, or intentional?
>>
>> In any event, you should be able to skip creating of function file for 
>> mmjam entirely, by defining the function as ...
>>
>>     dqadt = @(t,y) [qin - vmax/(1+km/(y/sz))]
>>
>> You can do that in mmjam0.m. This also allows  you to delete the 
>> "global" variables. I've attached a modification of your example that 
>> works for me (I'm running Octave 3.0.3).
>
>Thanks Ben,
>
>That certainly is much simpler!  I was just following a couple of 
>examples I found that had a separate function file but this does look 
>cleaner.  No idea why t was in the inputs .... just copied blindly!
>
>The example you send works well but the models I need to build will get 
>much more complex, i.e. many state variables (pools) and therefore many 
>(> 30 individual fluxes) fluxes.  It would be nice to specify the 
>individual flux equations somewhere separately from the individual 
>derivative equations as I've done in this example.  The problem  is that 
>now "y" is unspecified and gives the following error.  Is there a way to 
>specify the form of the equation outside the derivative equation statement?
>
>octave:24> mmsinglefile
>error: `y' undefined near line 20 column 26
>error: evaluating binary operator `/' near line 20, column 27
>error: evaluating binary operator `/' near line 20, column 24
>
>
>Thanks a bunch
>
>Jim

I'm not following you. What is in "mmsinglefile"?

Ben


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