[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Help-gsl] references for rk4imp and gear2 in version 1.13

From: Mohammad Akhlaghi
Subject: Re: [Help-gsl] references for rk4imp and gear2 in version 1.13
Date: Sun, 10 Dec 2017 20:05:25 +0100
User-agent: K-9 Mail for Android

Dear Gábor,

You don't need root access to build and install a different version of GSL (or 
any software) on a server. A complete description of how to do it is given here:

Following the names in that page, to compile your own programs with your GSL 
installation (not the server's), just add these two options to your compilation 
command (they are described in that page).



On December 10, 2017 7:34:32 PM GMT+01:00, Halasz Gabor <address@hidden> wrote:
>Dear Tuomo,
>Thank you for your answer.
>Actually I have found the reference for Gear's paper but never found an
>explanation what is the difference between  gear1 and gear2 in GSL.
>Actually all mentioning of Gear's method in new documents are similar
>to the following one:
>"the class of BDFs or commonly understood as Gear’s Method".
>But if it is a "class of methods" it would be nice if I can make it
>clear which variant I have used.
>I am using GSL on a server for which I have no root access, so I can
>not change the version as fast as I would like to publish our results.
>But despite of the old version, gear2 is an msbdf variant and bsimp is
>also available in this GSL version 1.13.
>Maybe there is a wider palette of suitable methods in the newer
>versions, but I am satisfied with the old version. Two of the methods
>provided the same results with high accuracy and these results are in
>agreement with the expectations. 
>Other methods provided very similar results for a wide range of the
>parameters. Usually they were faster and sometimes provided results
>even a bit closer to the "expectations".  But they failed --including
>rk2imp, gear1 or bsimp-- for the cases where I needed an extreme long
>Best regards,
>On 2017. december 10. 19:23:33 Tuomo Keskitalo wrote:
>> Hi,
>> for rk4imp I suggest this reference:
>> Ascher, U.M., Petzold, L.R., Computer methods for ordinary
>>     differential and differential-algebraic equations, SIAM,
>>     Philadelphia, 1998. ISBN 0898714125, 9780898714128
>> I think those old Gear methods are based on this reference:
>> Gear, C.W., Numerical Initial Value Problems in Ordinary Differential
>> Equations, 1971.
>> However, I guess you really don't want to use those old deprecated 
>> ode-initval methods. Instead, please updgrade to GSL version 2.4, use
>> ode-initval2, and try e.g. msbdf or bsimp methods, if your ODE system
>> stiff.
>> BR,
>> Tuomo
>> On 10.12.2017 13:48, Halasz Gabor wrote:
>> > Hello,
>> > 
>> > I have a problem with finding proper references and descriptions
>for some methods I have used for solving ODEs with GSL version 1.13.
>> > For the stepping functions gear1(2) the info page and the manuals
>only contain the following simple description: M=1(2) implicit Gear
>> > 
>> > I am especially interested in methods rk4imp and gear2 as all the
>other available ones in version 1.13  was not working properly for my
>> > 
>> > Best regards,
>> > Gábor
>> > 
>> > 
>> > 
>> > 

Sent from my Android device with K-9 Mail. Please excuse my brevity.

reply via email to

[Prev in Thread] Current Thread [Next in Thread]