id summary reporter owner description type status priority milestone component resolution keywords cc merged author reviewer upstream work_issues branch commit dependencies stopgaps
21758 Hold symbolic powers unevaluated if evaluation fails rws "Automatic evaluation of symbolic expressions of ""numerics"" prevents construction of such expressions despite them being perfectly numerically approximatable (or otherwise useful) if exact evaluation in the algebraic sense fails. This is usually not a problem with function expressions (because of the easily added `hold=True`), and sums and products (?), but powers have to be constructed awkwardly:
{{{
sage: SR(2) ^ SR(QQbar(sqrt(2)))
Traceback (most recent call last):
...
TypeError: no canonical coercion ...
sage: SR(2).power(SR(QQbar(sqrt(2))), hold=True)
2^1.414213562373095?
}}}
The ticket catches `TypeError`s in the first case and automatically uses the second form, to allow:
{{{
sage: SR(2) ^ SR(QQbar(sqrt(2)))
2^1.414213562373095?
}}}
" enhancement needs_work major sage-7.5 symbolics vdelecroix Ralf Stephan N/A u/rws/hold_symbolic_powers_unevaluated_if_evaluation_fails 49ab13301f5b44f946701f3fdcaff6c4613c0de7