On Tue, Apr 25, 2023 at 11:08:02PM -0700, 'Nasser M. Abbasi' via sage-devel wrote: > I read integrals from a file. They all are stored as strings. > > Then use SR('expression') inside sagemath to convert them to sagemath > symbolic expression before calling integrate. > > Some give parsing error. > > Is using SR('expression') not the correct way to convert string to a > symbolic expression? > > I am using 9.8 on Linux. Here is an example > > >sage > │ SageMath version 9.8, Release Date: 2023-02-11 │ > │ Using Python 3.11.1. Type "help()" for help. │ > > sage: hypergeometric((3/2,), (5/2, 3), -1/4*3^2) > hypergeometric((3/2,), (5/2, 3), -9/4) > > You see, there is no error. But now if put the expression inside string and > use SR, it gives error:
IMHO Sage gives no promise that the way an SR expression printed is always readable back as a string. Note that SR('hypergeometric([3/2,], [5/2, 3], -1/4*3^2)') works just fine. > > > sage: SR('hypergeometric((3/2,), (5/2, 3), -1/4*3^2)') > --------------------------------------------------------------------------- > SyntaxError Traceback (most recent call last) > File ~/TMP/sage-9.8/src/sage/symbolic/expression.pyx:13706, in > [...] > SyntaxError: Mismatched parentheses > > During handling of the above exception, another exception occurred: > > [...] > > > > Is this a bug or Am I doing something wrong? This happens on very few > cases, not all the time. The above is an example where SR gives an error. What are other examples which give errors like this? Perhaps hypergeomertic() should come with a special __repr__() function to show the 1st two arguments as lists rather than in its internal representation as tuples. (Or should it be _repr_() ? ) Dima > > Thanks > --Nasser > > -- > You received this message because you are subscribed to the Google Groups > "sage-devel" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sage-devel+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/sage-devel/eeec7521-c567-4870-8442-e3eed439b32dn%40googlegroups.com. -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/sage-devel/ZEjublNs6yanwgLv%40chronos.pasechnik.info.
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