RuntimeError: ECL says: THROW: The catch MACSYMA-QUIT is undefined.

[Eviatar]

I'm getting a strange error with the following command:

find_maximum_on_interval(-x^2 + 9*x, 4.4, 8)

this returns the error:

RuntimeError: ECL says: THROW: The catch MACSYMA-QUIT is undefined.

I tried this on 4.7.2, 4.7.1, and on the single-cell server, and the same thing occurs.

[Nils Bruin]

The documentation of find_maximum_on_interval shows this is a
numerical function that is not prepared to take symbolic expressions.
However, the error message is deplorable. Ticket:

http://trac.sagemath.org/sage_trac/ticket/12032

[Eviatar]

Oh, I see. However, this is not made explicit in the documentation, and it does work with symbolics sometimes. For example,

find_maximum_on_interval(-x^2 + 9*x, 1, 3)