Blurb::Specifies the diagonal matrix format when specifying a
user-specified proposal covariance.

Description::

When specifying the MCMC proposal covariance in an input file, this
keyword declares the use of a diagonal matrix format, i.e., the user
only provides the (positive) values along the diagonal.

Topics::

Examples::
\verbatim
method,									
        bayes_calibration queso
         samples = 1000 seed = 348
          dram
          proposal_covariance
            diagonal values 1.0e6 1.0e-1
\endverbatim

Theory::
Faq::
See_Also::
