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Originally Posted by: Razonar  I can't reproduce this in SMath. 1/1 in Smath 6179, proof: the snippet. Cheers Alvaro   Integrate with ode solver.sm (30kb) downloaded 35 time(s).
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Originally Posted by: Razonar I can't reproduce this in SMath. You may not be able to implement the Mathcad bloc Given/ODEsolve. ODEsolve is based on linterp. That is the first point. The other point is that in Mathcad "linterp(x)" is a scalar function. In Smath: ainterp, cinterp, linterp are simply interpolation fncts They are not scalar functions. How does it reflects in ODEsolve ? In Smath, ln(x), exp(x), ... are scalar from source code. I tried to make cinterp scalar like in Mathcad, not to avail. Please, persist on such a beautiful idea.
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Originally Posted by: Jean Giraud I tried to make cinterp scalar like in Mathcad, not to avail. This document was essentially designed to plot scalar the derivative on canvas, as well as get a discrete export. Also included: the scalar quadratic. Cheers ... Jean Spline Deriv Infinitesimal.sm (71kb) downloaded 32 time(s).
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Originally Posted by: Jean Giraud
You may not be able to implement the Mathcad bloc Given/ODEsolve.
Hi Jean. Actually not, just the solver, without the given. I found how to call the odesolver, with D(x,y)=[f(x)]. This method is much more faster than the direct integration. But remains the ln(0) error, which seems to be a bug in the odesolvers, because zero isn't in the domain range.  Integrate with ode solver.sm (11kb) downloaded 36 time(s).Best regards. Alvaro. Edited by user 30 November 2018 08:33:22(UTC)
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The zero point is used to determine the dimension of the vector D(t,x) at runtime (D(0, x0)). The size of the system must be determined for the further operation of the numerical algorithm. It seems that it would be correct to substitute the beginning of the interval. I will try to change this. Also, if possible, I will support the one-dimensional case. |
Russia ☭ forever
Viacheslav N. Mezentsev |
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on 30/11/2018(UTC), on 30/11/2018(UTC), on 30/11/2018(UTC), on 30/11/2018(UTC)
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Thanks Viacheslav. It's amazing the effort that you and the others plugins developers put in enhance SMath, with very spectacular results.
Best regards.
Alvaro.
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Originally Posted by: Razonar Hi Jean. Actually not, just the solver, without the given.
I found how to call the odesolver, with D(x,y)=[f(x)].
This method is much more faster than the direct integration.
But remains the ln(0) error, which seems to be a bug in the odesolvers, because zero isn't in the domain range. Buenos dias Alvaro ! ln(0) was introduced in Mathcad 11 soon after release via update [from recollection] There is more in the attached, specially wrt parametric D(,,,). Jean  ODE 0_Model General.sm (30kb) downloaded 24 time(s).
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on 30/11/2018(UTC), on 30/11/2018(UTC), on 04/12/2018(UTC)
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