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Significant improvement to gvar.dump/load and some new functions.
All changes are backwards compatible. Note that this code
still works with Python 2.7 (as well as Python 3.X, of course)
but it seems likely this will not continue far into
the future, as developers for the several packages
used by gvar abandon Python2, now that it is formally
discontinued.
- New versions of gvar.dump and gvar.dumps that can preserve
dependencies between derived and primary GVars (to allow, for
example, the construction of error budgets). Update for
pickling of gvar.BufferDicts.
- New function gvar.qqplot() for making QQ-plots.
- Slight modification of gvar.chi2() to support
implementation of gvar.qqplot().
- New function gvar.is_primary(g) to determine whether GVars
are primary or derived. Also gvar.GVar.is_primary(). Also
new function gvar.dependencies for collecting relevant
primary GVars.
- Function gvar.deriv(g, x) now works for an array x of GVars
(not just a single GVar). Also gvar.GVar.deriv(x).
- Fixed bug (that caused crashes) in (undocumented) low-level
gvar.gvar() usage.