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 Lagged Tau
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::

    SUPG Lagged Tau = {yes | no}

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Description / Usage
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Lag the  SUPG :math:`\tau`  (se the value fromt he previous step values).


yes
    Lag the :math:`\tau` computation
no
    Use the current step to compute :math:`\tau`

The default value is **no**.

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Examples
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The following is a sample card:
::

    SUPG Lagged Tau = yes

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Technical Discussion
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