Feature #801
Test whether a symbol is in a ring
Description
Should there be a function which tests whether a given symbol
is in given ring
?
I am thinking of "recursive" semantics: check whether the symbol is an indet, if not check whether it is in the coeff ring.
What should be the type of the result? Boolean?
Related issues
History
#1 Updated by John Abbott over 8 years ago
Currently this operation is implemented in a hidden way inside RingBase::myNew(symbol)
.
The implementation there needs to be improved (as it can be slow when the ring contains many symbols); it also creates a "wasteful" copy of the list of all symbols in the ring.
Current the pseudo-ctor for a RingElem
from a symbol
produces either a RingElem
or throws an exception. Note that the RingElem
produced could be zero (or almost any other value): consider the image of x
in the quotient ring ZZ[x,y]/(x)
.
Should the new function return a boolean?
#2 Updated by Anna Maria Bigatti over 8 years ago
- Target version changed from CoCoALib-0.99540 Feb 2016 to CoCoALib-0.99550 spring 2017
#3 Updated by John Abbott almost 8 years ago
- Target version changed from CoCoALib-0.99550 spring 2017 to CoCoALib-0.99560
#4 Updated by John Abbott over 6 years ago
- Target version changed from CoCoALib-0.99560 to CoCoALib-0.99600
#5 Updated by John Abbott over 6 years ago
- Related to Slug #881: ReadExpr is too slow on large polys added
#6 Updated by John Abbott about 6 years ago
- Target version changed from CoCoALib-0.99600 to CoCoALib-0.99650 November 2019
#7 Updated by John Abbott almost 5 years ago
- Target version changed from CoCoALib-0.99650 November 2019 to CoCoALib-0.99700
#8 Updated by John Abbott over 4 years ago
- Target version changed from CoCoALib-0.99700 to CoCoALib-0.99800
#9 Updated by John Abbott over 2 years ago
- Target version changed from CoCoALib-0.99800 to CoCoALib-0.99850
#10 Updated by John Abbott 4 months ago
- Target version changed from CoCoALib-0.99850 to CoCoALib-0.99880