The optimal error estimate and superconvergence of the local discontinuous Galerkin methods for one-dimensional linear fifth order time dependent equations
In this paper, we investigate the optimal error estimate and the superconvergence of linear fifth order time dependent equations. We prove that the local discontinuous Galerkin (LDG) solution is i35" class="mathmlsrc">i35.gif&_user=111111111&_pii=S089812211630298X&_rdoc=1&_issn=08981221&md5=a54fc5cb595f5369897452fdaf90d9e6" title="Click to view the MathML source">(k+1)th order convergent when the piecewise i36" class="mathmlsrc">i36.gif&_user=111111111&_pii=S089812211630298X&_rdoc=1&_issn=08981221&md5=b7294b59ddbfaf24b1131737f9985a82" title="Click to view the MathML source">Pk space is used. Also, the numerical solution is i37" class="mathmlsrc">i37.gif&_user=111111111&_pii=S089812211630298X&_rdoc=1&_issn=08981221&md5=c01ac2026c2844eee7b2ae1ee5d822d4">lineImage" height="21" width="49" alt="View the MathML source" title="View the MathML source" src="/sd/grey_pxl.gif" data-inlimgeid="1-s2.0-S089812211630298X-si37.gif">th order superconvergent to a particular projection of the exact solution. The numerical experiences indicate that the order of the superconvergence is i38" class="mathmlsrc">i38.gif&_user=111111111&_pii=S089812211630298X&_rdoc=1&_issn=08981221&md5=355d3358ab586d7596c8c90ec6a4c4ec" title="Click to view the MathML source">(k+2), which implies the result obtained in this paper is suboptimal.