How to address the domain of an outputed interpolating function

Question

I am solving a system of ODEs with DSolve, which returns the results as interpolating functions. The solver always stops after some finite time because of resolution issues, so the domain of the outputted interpolating function is limited.

Hence, if I then plot those functions with a Plot command, I have to specify the range {t,0,tmax}. However tmax would change a bit everytime I run the DSolve command, and it is a pain to always change tmax manually.

Is there a way to address the domain of such a function directly?

Possible duplicate: https://mathematica.stackexchange.com/questions/28337/whats-inside-interpolatingfunction1-4 — Michael E2, Mar 27 '19 at 01:51
Also related: (19042), (35310), (55881), (57854), (87525), (147997), (154293) -- The method ifn["Domain"] is used. — Michael E2, Mar 27 '19 at 02:08

score 3 · Accepted Answer · answered Mar 26 '19 at 15:37

3

You can get the domain of an interpolation-object quite simple.

For example the simulation timerange of

sol = NDSolveValue[{x'[t] == -x[t], x[0] == 1, WhenEvent[x[t] < .5, "StopIntegration"]}, x, {t, 0, 1}]

is

sol["Domain"][[1]]
(*{0., 0.693147}*)

answered Mar 26 '19 at 15:37

Ulrich Neumann

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Perfect, thanks! – Britzel Mar 26 '19 at 16:02
You're welcome! – Ulrich Neumann Mar 26 '19 at 16:05
Short followup question: Is it possible to remove the { } around those two numbers in a simple way? I know I could address now each element of that list. But perhaps there is a smarter solution. – Britzel Mar 26 '19 at 16:11
Perhaps {t0,t1}= sol["Domain"][[1]]? – Ulrich Neumann Mar 26 '19 at 16:18
Suppose that works, thanks a lot! – Britzel Mar 28 '19 at 21:04

How to address the domain of an outputed interpolating function

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