  Rank: Advanced Member Groups: Registered, Advanced Member Joined: 10/11/2010(UTC) Posts: 1,342   Was thanked: 1174 time(s) in 676 post(s)
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lsoda (Livermore Solver for Ordinary Differential Equations)  Functions list:
lsoda(5) - (ics,tmin,tmax,steps,D(t,x)) solves the initial value problem for stiff or nonstiff systems. lsoda(3) - (ode,y(x),xmax) solves the initial value problem for stiff or nonstiff systems. lsoda(4) - (ode,y(x),xmax,steps) solves the initial value problem for stiff or nonstiff systems.
lsoda(ics, xmin, xmax, steps, ode) solves the initial value problem for stiff or nonstiff systems (uses Adams/BDF methods). Arguments:
- ics is either a vector of n real initial values, where n is the number of unknowns (or a single scalar initial value, in the case of a single ODE).
- xmin and xmax are real, scalar endpoints of the interval over which the solution to the ODE(s) is evaluated. Initial values in init are the values of the ODE function(s) evaluated at x1.
- steps is the integer number of discretization intervals used to interpolate the solution function. The number of solution points is the number of intervals + 1.
- ode is a vector function of the form D(x,y) specifying the right-hand side of the system
Options: - AbsTol - absolute tolerance parameter, default value 10⁻⁷. - RelTol - relative tolerance parameter, default value 10⁻⁴. Links: 1. Solving Stiff ODEs. 2. Serial Fortran Solvers for ODE Initial Value Problems. lsoda.integrate.sm (11kb) downloaded 56 time(s). lsoda.kinetic1.sm (8kb) downloaded 40 time(s). lsoda.kinetic2.sm (11kb) downloaded 34 time(s). lsoda.kinetic3.sm (11kb) downloaded 32 time(s). lsoda.test1.sm (12kb) downloaded 34 time(s). lsoda.test2.sm (12kb) downloaded 32 time(s). lsoda.Arenstorf Orbit.sm (16kb) downloaded 52 time(s). lsoda.Amplitude detector.sm (21kb) downloaded 35 time(s). lsoda.integrate.pdf (88kb) downloaded 60 time(s). lsoda.kinetic1.pdf (75kb) downloaded 44 time(s). lsoda.kinetic2.pdf (88kb) downloaded 41 time(s). lsoda.kinetic3.pdf (83kb) downloaded 41 time(s). lsoda.test1.pdf (88kb) downloaded 54 time(s). lsoda.test2.pdf (91kb) downloaded 37 time(s). lsoda.Arenstorf Orbit.pdf (94kb) downloaded 53 time(s). lsoda.Amplitude detector.pdf (149kb) downloaded 40 time(s).See also:● Mathcad Toolbox● DotNumerics● SADEL● Matlab C++ Math Library● OSLO● GNU Scientific Library (GSL)Edited by user 23 December 2021 20:25:02(UTC)
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Russia ☭ forever Viacheslav N. Mezentsev |
 4 users thanked uni for this useful post.
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on 21/01/2019(UTC), on 21/01/2019(UTC), on 21/01/2019(UTC), on 21/01/2019(UTC)
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  Rank: Advanced Member Groups: Registered
Joined: 19/11/2020(UTC) Posts: 34   Location: Ireland Was thanked: 1 time(s) in 1 post(s)
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Hello Viacheslav, I attach here the two different file, lsodaMAP3 have the problem solved, lsodaMAP2 show the error. SMath version 0.99.7610.506 lsoda version 0.1.7175.9902 lsoda MAP2.sm (49kb) downloaded 19 time(s). lsoda MAP3.sm (52kb) downloaded 13 time(s). crash.pdf (79kb) downloaded 14 time(s).Playing a little bit in the lsodaMAP2 I was able to make it show the chart with the "problem".  Let me know if you need anything else! All the best Francesco Edited by user 02 December 2020 18:46:19(UTC)
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Veniamo da molto lontano e andiamo molto lontano! Palmiro Togliatti |
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  Rank: Advanced Member Groups: Registered, Advanced Member Joined: 10/11/2010(UTC) Posts: 1,342   Was thanked: 1174 time(s) in 676 post(s)
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The problem is in the X-Y Plot plugin. It cannot display the input data because it is outside the normal bounds. Also in the document somehow the min and max values of the axis are the same, which also results in an error. It will take a time to fix this. I haven't tested the plugin on bad data much. |
Russia ☭ forever Viacheslav N. Mezentsev |
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  Rank: Advanced Member Groups: Registered, Advanced Member Joined: 10/11/2010(UTC) Posts: 1,342   Was thanked: 1174 time(s) in 676 post(s)
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 Plugin updated. Changes: - added support for ODE systems in mathematical form; - refactored. |
Russia ☭ forever Viacheslav N. Mezentsev |
 1 user thanked uni for this useful post.
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  Rank: Advanced Member Groups: Registered, Advanced Member Joined: 10/11/2010(UTC) Posts: 1,342   Was thanked: 1174 time(s) in 676 post(s)
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 Plugin updated. Changes: - solution restructured; - converting the task for the ODE solver to the numerical form is now performed through the Mathcad Toolbox plugin (to avoid code duplication), so it must be installed; - refactored. Solvers that support mathematical notation now reuse code from the Mathcad Toolbox plugin. Now there is no need to recompile every such plugin. As far as I understand, the algorithm used in this solver is the same as used in Odesolve: Adams/BDF. This can be seen from the comments in the source code. If I can port this code to c#, then we will have the same solver as in Mathcad. I want to include it as a default solver in Mathcad Toolbox plugin. |
Russia ☭ forever Viacheslav N. Mezentsev |
 1 user thanked uni for this useful post.
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