## 16 Reputation

18 years, 23 days

## Abserr/Maxmesh...

My thanks to Prof. Meade and Prof. Harrington for their suggestions on how to increase "maxmesh" or "abserr". Prof. Harrington's suggestion about adding 'maxmesh=500' as an option in dsolve didn't pan out, but I'll try other numbers--I understand the maximum is about 8000 plus. Prof. Meade's suugestion about adding "abserr=1e-4" also didn't pan out (on my Maple 9.5--Prof.Meade seems to be using Maple 10,though this shouldn't make a difference,methinks!) However,adding abserr=1e-3 as an option to dsolve DOES work! Very strange indeed. Anyway,I've got my graph,and thanks again to Prof. Meade et al.

## How to increase "maxmesh" in Maple...

Hello , I have been trying to plot the solution to a boundary layer problem using Maple via the following programme: >BVP:={0.1*diff(y(x),[x\$2]) + (x^0.5)*diff(y(x),x) - y(x) = 0, y(0)=0,y(1)=exp(2)}; >J:=dsolve(BVP,y(x), type=numeric,method=bvp[midrich]); >plots[odeplot](J,[x,y(x)], 0..1,color=blue,style=line,symbol=circle, symbolsize=12); However,before I can write the instructions to plot, I get an error message saying: "Error,(in dsolve/numeric,bvp) unable to achieve requested accuracy of 0.1e-5 with maximum 128 point mesh (was able to get 0.17e-4), consider increasing "maxmesh" or using larger "abserr" ."

## How to increase maxmesh in Maple 9.5...

Hello , I have been trying to plot the solution to a boundary layer problem using Maple via the following programme: >BVP:={0.1*diff(y(x),[x\$2]) + (x^0.5)*diff(y(x),x) - y(x) = 0, y(0)=0,y(1)=exp(2)}; >J:=dsolve(BVP,y(x), type=numeric,method=bvp[midrich]); >plots[odeplot](J,[x,y(x)], 0..1,color=blue,style=line,symbol=circle, symbolsize=12); However,before I can write the instructions to plot, I get an error message saying: "Error,(in dsolve/numeric,bvp) unable to achieve requested accuracy of 0.1e-5 with maximum 128 point mesh (was able to get 0.17e-4), consider increasing "maxmesh" or using larger "abserr" ."
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