Doctest fix for: dilog(RR) should return an element of RR

[zimmermann6]

in Sage 6.10:

sage: dilog(-1.0)
-1/12*pi^2
sage: dilog(1)
1/6*pi^2
sage: dilog(0.5)
1/12*pi^2 - 1/2*log(2)^2

we should not get symbolic output with floating-point input.

Reported as pynac/pynac#219

Upstream: Reported upstream. Developers acknowledge bug.

Component: basic arithmetic

Issue created by migration from https://trac.sagemath.org/ticket/19906

[rwst]

Description changed:

--- 
+++ 
@@ -10,4 +10,4 @@
 ```
 we should not get symbolic output with floating-point input.
 
-
+Reported as https://github.com/pynac/pynac/issues/219

[rwst]

Upstream: Reported upstream. Developers acknowledge bug.

[rwst]

Branch: u/rws/dilog_rr__should_return_an_element_of_rr

[rwst]

Commit: 896bdc7

[rwst]

Dependencies: pynac-0.7.2

[rwst]

comment:3

This is fixed in Pynac git master. This ticket has doctests but they depend on a pynac-0.7.2 upgade.

---

New commits:

896bdc7

19906: doctest fix for: dilog(RR) should return an element of RR

[rwst]

Changed dependencies from pynac-0.7.2 to #21963

[videlec]

comment:5

You need to set your name in the Authors field.

[videlec]

comment:6

Could you be more careful and actually check the parent of the output? In other words something like

sage: y = dilog( RealField(13)(1.0))
sage: assert parent(y) is RealField(13)
sage: y = dilog( RealField(100)(1.0))
sage: assert parent(y) is RealField(100)

I don't know to which extent this function is available on intervals, balls and complexes but they should be tested as well with various precision.