Unable to parse hypergeometric result from mathematica_free

[mforets]

sage: integrate(e^(-x^2)*log(x), x, algorithm='mathematica_free')
Traceback (most recent call last):
...
ValueError: Unable to parse: -(x*HypergeometricPFQ[{1/2,1/2},{3/2,3/2},-x^2])+(Sqrt[Pi]*Erf[x]*Log[x])/2

[mforets]

the result i was expecting is the sage object:

result = -(x*hypergeometric((1/2,1/2),(3/2,3/2),-x^2))+(sqrt(pi)*erf(x)*log(x))/2

maybe one can substitute the line in mma_free_integrator:

ans = SR(mexpr.lower().replace('[', '(').replace(']', ')'))

with the some of the code at the mathematica interface in _sage_ ?

(we don't need Mathematica to be installed!)

[mforets]

New commits:

​624f0e3	error func mathematica conversion
​83c1dfc	use mathematica symbols table

[git]

Branch pushed to git repo; I updated commit sha1. New commits:

​017571b	add 2 mathematica conversions
​ccc99a1	tweak import as

[git]

Branch pushed to git repo; I updated commit sha1. New commits:

​686f1ca

fix extra space in message

[mforets]

notice that this change has an (arguably) adverse effect in test at lines 492-495 of symbolic/integration/integral.py.

indeed, instead of

sage: _ = var('x, y, z')
sage: f = sin(x^2) + y^z
sage: f.integrate(x, algorithm="mathematica_free")   # optional - internet
x*y^z + sqrt(1/2)*sqrt(pi)*fresnels(sqrt(2)*x/sqrt(pi))

one has:

sage: _ = var('x, y, z')
sage: f = sin(x^2) + y^z
sage: f.integrate(x, algorithm="mathematica_free")   # optional - internet
Traceback (most recent call last):
NotImplementedError: Don't know a Sage equivalent for Mathematica function 'FresnelS'.

the new issue is because Fresnel integrals are not implemented in Sage (right?) -- in other words, one cannot do much with the former result.

That said, Sage could return a more verbose message like:

"Don't know a Sage equivalent for Mathematica function '%s'.

Unable to parse: %s" % m.group() % mexpr

[rws]

Replying to mforets:

the new issue is because Fresnel integrals are not implemented in Sage (right?)

Right. You can see all symbolic function tickets at ​https://trac.sagemath.org/wiki/symbolics/functions

[mforets]

thanks for pointing out that page. i've added an entry in ​Tickets to make for future reference.

[rws]

Looks good, and tests in relevant directories pass. Please fill in the Authors field.

[mforets]

Thanks :)

[mforets]

do you want me to update (in a new ticket) the doctest from comment:5? the patchbots, do they test with optional - internet?

[vbraun]

merge conflict

[rws]

New commits:

​49bb25e

Merge branch 'develop' into t/22998/22998