Blurb::
Suppresses output of sensitivity indices with values lower than this tolerance

Description::
The \c drop_tolerance keyword allows the user to specify a value below
which sensitivity indices generated by \c variance_based_decomp are
not displayed. 

<b> Default Behavior </b>

By default, all sensitivity indices generated by \c
variance_based_decomp are displayed.

<b> Usage Tips </b>

For \c polynomial_chaos, which outputs main, interaction, and total
effects by default, the \c univariate_effects may be a more
appropriate option.  It allows suppression of the interaction effects
since the output volume of these results can be prohibitive for high
dimensional problems. Similar to suppression of these interactions is
the covariance control, which can be selected to be
diagonal_covariance or full_covariance, with the former supporting
suppression of the off-diagonal covariance terms (to save compute and
memory resources and reduce output volume).

Topics::
Examples::
\verbatim
method,
  sampling
    sample_type lhs
    samples = 100
    variance_based_decomp
    drop_tolerance = 0.001
\endverbatim
Theory::
Faq::
See_Also::	
