Hello everyone, I am conducting a convergence study on the L2 norm of the error using the ‘errornorm’ function for polynomial orders 1, 2, 3 and 4. I am noticing that as soon as the L2 error for polynomials of order 4 is expected to drop below 10^-11 on a given grid, I start losing convergence. Did…

Thank you Nate. Do you know though of any back of the envelop calculation to determine the smallest sized grid that I run a simulation on given a certain polynomial order and a starting residual? Thanks again.

Round-off errors relative to mesh size and polynomial order

mathematics

nate October 13, 2021, 9:25pm 2

You’ve hit machine precision.

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Round-off errors relative to mesh size and polynomial order

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