PDE
in [Matlab]
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From: Nga Do on 26 Feb 2010 03:53 Good afternoon, I am using PDEs to solve the mathematic problem, heat and mass transfer. However, i met this mistake, how can i overcome it? can you help me? Warning: Failure at t=0.000000e+000. Unable to meet integration tolerances without reducing the step size below the smallest value allowed (7.905050e-323) at time t. > In ode15s at 753 In pdepe at 320 Warning: Time integration has failed. and ??? Attempted to access sR(1); index out of bounds because numel(sR)=0. i am waiting for you reply. Regards.
From: Torsten Hennig on 25 Feb 2010 20:03 > Good afternoon, > > I am using PDEs to solve the mathematic problem, heat > and mass transfer. However, i met this mistake, how > can i overcome it? can you help me? > Warning: Failure at t=0.000000e+000. Unable to meet > integration > tolerances without reducing the step size below the > smallest value > allowed (7.905050e-323) at time t. > > In ode15s at 753 > In pdepe at 320 > > Warning: Time integration has failed. > > and > > ??? Attempted to access sR(1); index out of bounds > because > numel(sR)=0. > > > i am waiting for you reply. > ... and we are waiting for your code. > Regards. Best wishes Torsten.
From: Luca Zanotti Fragonara on 26 Feb 2010 06:57 It can depend bot from the coefficients of your ODE or a possible mistake in your set of differential equations. If the problem is higly-non linear is possible that the solver doesn't reach a solution because it needs a dt too little.
From: tulipvn85 on 27 Feb 2010 03:52 On Feb 26, 7:03 pm, Torsten Hennig <Torsten.Hen...(a)umsicht.fhg.de> wrote: > > Good afternoon, > > > I am using PDEs to solve the mathematic problem, heat > > and mass transfer. However, i met this mistake, how > > can i overcome it? can you help me? > > Warning: Failure at t=0.000000e+000. Unable to meet > > integration > > tolerances without reducing the step size below the > > smallest value > > allowed (7.905050e-323) at time t. > > > In ode15s at 753 > > In pdepe at 320 > > > Warning: Time integration has failed. > > > and > > > ??? Attempted to access sR(1); index out of bounds > > because > > numel(sR)=0. > > > i am waiting for you reply. > > .. and we are waiting for your code. > > > Regards. > > Best wishes > Torsten.- Hide quoted text - > > - Show quoted text - oh, i just see that The hardest one to debug is if you have used / instead of ./ somewhere in a function. If you integrate the function, this may cause quad to give a very odd error message: ??? Attempted to access y(7); index out of bounds because numel(y)=1. How can i overcome that mistake, i do not think i used / instead ./
From: Torsten Hennig on 26 Feb 2010 20:31
> On Feb 26, 7:03 pm, Torsten Hennig > <Torsten.Hen...(a)umsicht.fhg.de> > wrote: > > > Good afternoon, > > > > > I am using PDEs to solve the mathematic problem, > heat > > > and mass transfer. However, i met this mistake, > how > > > can i overcome it? can you help me? > > > Warning: Failure at t=0.000000e+000. Unable to > meet > > > integration > > > tolerances without reducing the step size below > the > > > smallest value > > > allowed (7.905050e-323) at time t. > > > > In ode15s at 753 > > > In pdepe at 320 > > > > > Warning: Time integration has failed. > > > > > and > > > > > ??? Attempted to access sR(1); index out of > bounds > > > because > > > numel(sR)=0. > > > > > i am waiting for you reply. > > > > .. and we are waiting for your code. > > > > > Regards. > > > > Best wishes > > Torsten.- Hide quoted text - > > > > - Show quoted text - > > oh, i just see that > > The hardest one to debug is if you have used / > instead of ./ somewhere > in a function. If you integrate the function, this > may cause quad to > give a very odd error message: > ??? Attempted to access y(7); index out of bounds > because numel(y)=1. > > How can i overcome that mistake, i do not think i > used / instead ./ With my answer I wanted to say: We cannot answer your questions if we do not see exactly what you coded. Best wishes Torsten. |