bugs in evaluation of spherical bessel function

[williamstein]

BUG 1:

Hi,
I was just trying to calculate some stuff with spherical Bessel
functions and got this error message:

sage: spherical_bessel_J(3,.1)


....
6823         return x
  6824     except SyntaxError:
-> 6825         raise TypeError, "unable to make sense of Maxima
expression '%s' in SAGE"%s
  6826     finally:
  6827         is_simplified = False

<type 'exceptions.TypeError'>: unable to make sense of Maxima
expression '9.5185197208655641L-6' in SAGE
sage:
KeyboardInterrupt

I checked it, it happens for small values of the argument x.
Does anyone has a solution or work around?

Greets,

schorsch

BUG2

sage: spherical_bessel_J(3,.1, algorithm='scipy')
---------------------------------------------------------------------------
<type 'exceptions.NameError'>             Traceback (most recent call last)

/Users/was/Downloads/z/<ipython console> in <module>()

/Users/was/build/sage-2.10.3.rc3/local/lib/python2.5/site-packages/sage/functions/special.py in spherical_bessel_J(n, var, algorithm)
    782         ans = ans.replace(")","")
    783         ans = ans.replace("j","*I")
--> 784         return sage_eval(ans)
    785     elif algorithm == 'maxima':
    786         _init()

/Users/was/build/sage-2.10.3.rc3/local/lib/python2.5/site-packages/sage/misc/sage_eval.py in sage_eval(source, locals)
    108     p = preparse(source)
    109     try:
--> 110         return eval(p, sage.all.__dict__, locals)
    111     except SyntaxError, msg:
    112         raise SyntaxError, "%s\nError using SAGE to evaluate '%s'"%(msg, p)

/Users/was/Downloads/z/<string> in <module>()

<type 'exceptions.NameError'>: name 'array' is not defined

Probably many of the special functions in functions/special.py have similar bugs.

Component: numerical

Author: Mike Hansen

Reviewer: Alex Ghitza

Merged: sage-4.3.2.alpha0

Issue created by migration from https://trac.sagemath.org/ticket/2494

[aghitza]

comment:2

Note that BUG 1 has disappeared in sage-4.1.1:

sage: spherical_bessel_J(3,.1)
9.51851972087e-06

BUG 2 is still there.

[mwhansen]

Author: Mike Hansen

[mwhansen]

comment:3

Attachment: trac_2494.patch.gz

[aghitza]

Reviewer: Alex Ghitza

[aghitza]

comment:4

Looks good and passes tests.

[sagetrac-mvngu]

Merged: sage-4.3.2.alpha0