How do I increase the number of mesh points that bvp5c uses?

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Mark 2013-4-4

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https://ww2.mathworks.cn/matlabcentral/answers/69900-how-do-i-increase-the-number-of-mesh-points-that-bvp5c-uses

编辑： Christian Chamberlayne 2020-9-17

I'm trying to solve a 2nd order differential equation using bvp5c. It can get moderately stiff for certain parameters.

I get the following warning.

Warning: Unable to meet the tolerance without using more than 5000 mesh points. The last mesh of 892 points and the solution are available in the output argument. The maximum error is 0.00120499, while requested accuracy is 1e-07. > In bvp5c at 339

How can I increase the number of mesh points beyond 5000?

Thanks.

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Answer 1

Jan 2013-4-5

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https://ww2.mathworks.cn/matlabcentral/answers/69900-how-do-i-increase-the-number-of-mesh-points-that-bvp5c-uses#answer_81087

编辑：Jan 2013-4-5

在 MATLAB Online 中打开

Please take the time to read the documentation of bvp5c. There you find the link to the function to set the options http://www.mathworks.com/help/matlab/ref/bvpset.html, where the parameter "NMax" is explained:

Maximum number of mesh points allowed when solving the BVP, ...

Of course this message has the strong meta-message, that it is recommended to read the help and doc information before asking the forum. Matlab's docs are very useful and complete, and they have a much higher quality than the manuals of other software manufacturers.

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Christian Chamberlayne 2020-9-17

编辑：Christian Chamberlayne 2020-9-17

I also ended up here after trying to figure out the documetation.

Thank you for linking the bvpset function documetntation.

About your meta message: the max mesh size and how to change it is not particularly obvious on the bvp4c (and bvp5c) documentation. Even knowing to go look up the bvpset function is not imediately obvious from the bvp4c documentaion.

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