Possible inconsistency in symbolic limits

asked 2021-01-20 02:58:40 +0100

cav_rt
494 ●9 ●24

updated 2023-01-09 23:59:54 +0100

tmonteil
27423 ●31 ●204 ●517 http://wiki.sagemath.o...

I was trying to manipulate some symbolic expressions and got an unexpected error. Here is a minimal example,

u=integrate(x**3/(exp(x)-1),(x,0,oo))

The expression is quite messy, but the result is known. When I try to use any simplification routine, like

u.simplify()

sage displays the error message

RuntimeError: ECL says: Error executing code in Maxima: limit: direction must be either 'plus' or 'minus'; found: _SAGE_VAR_minus

As far I understood, the expression is defining lateral limits by symbolic variables, while maxima handle such limits as strings. If it is the case there is an internal conflict here. Is it the case?

edit retag flag offensive close merge delete

add a comment

Comments

Smaller display of the same bug:

sage: maxima('limit(polylog(4,e^x),x,+Infinity,minus)').sage()                  
limit(polylog(4, _e^x), x, +Infinity, minus)
sage: _.simplify()

FrédéricC ( 2021-01-20 10:26:07 +0100 )edit

Thank you!

cav_rt ( 2021-01-20 21:48:55 +0100 )edit

add a comment

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Possible inconsistency in symbolic limits

1 Answer

Comments

Your Answer

Question Tools

Stats

Related questions

Possible inconsistency in symbolic limits edit

1 Answer

Comments

Your Answer

Question Tools

Stats

Related questions

Possible inconsistency in symbolic limits