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Mostly internal changes needed by other code.
- Improved internal treatment of sparse covariance matrices in
gvar.svd (more sparse now). This involved improvements in svec and smat,
which now look for and remove entries that are 0; and it involved a new
function evalcov_blocks that constructs the non-zero block diagonals of the
covariance matrix (as opposed to the entire matrix, which is what evalcov
does). This should lead to small speedups but also greatly reduce memory
consumption in cases where evalcov was used to construct covariance matrices
for large numbers of GVars (eg, lsqfit).
- Two new convenience functions: cov(g1,g2) which is evalcov([g1,g2])[0,1]
and corr(g1,g2) which returns evalcorr([g1,g2])[0,1].
- gvar.ranseed now accepts single integers, as well as lists of
integers, as an argument.
- New low-level routines gvar.disassemble and gvar.reassemble
that should be used with care.
- changed gvar.chi2() so its output can be formatted with
gvar.fmt_chi2().