Hello, sorry if this is basic question, but I just started yesterday using sage.
When I set algorithm to sympy, I get strange error. But for all other algorithms, it works ok. May be because I am using beta version? SageMath version 8.3.beta5, Release Date: 2018-06-09
var('t')
sage: integrate(log(t)/(t + 1),t, algorithm="maxima")
log(t + 1)*log(t) + dilog(-t)
sage: integrate(log(t)/(t + 1),t, algorithm="fricas")
integral(log(t)/(t + 1), t)
sage: integrate(log(t)/(t + 1),t, algorithm="giac")
integrate(log(t)/(t + 1), t)
sage: integrate(log(t)/(t + 1),t, algorithm="sympy")
gives
AttributeError Traceback (most recent call last)
<ipython-input-18-636e47034533> in <module>()
----> 1 integrate(log(t)/(t + Integer(1)),t, algorithm="sympy")
/usr/lib/python2.7/site-packages/sage/misc/functional.py in integral(x, *args, **kwds)
751 """
752 if hasattr(x, 'integral'):
--> 753 return x.integral(*args, **kwds)
754 else:
755 from sage.symbolic.ring import SR
/usr/lib/python2.7/site-packages/sage/symbolic/expression.pyx in sage.symbolic.expression.Expression.integral (build/cythonized/sage/symbolic/expression.cpp:69762)()
12345 R = ring.SR
12346 return R(integral(f, v, a, b, **kwds))
> 12347 return integral(self, *args, **kwds)
12348
12349 integrate = integral
/usr/lib/python2.7/site-packages/sage/symbolic/integration/integral.py in integrate(expression, v, a, b, algorithm, hold)
814 if not integrator:
815 raise ValueError("Unknown algorithm: %s" % algorithm)
--> 816 return integrator(expression, v, a, b)
817 if a is None:
818 return indefinite_integral(expression, v, hold=hold)
/usr/lib/python2.7/site-packages/sage/symbolic/integration/external.py in sympy_integrator(expression, v, a, b)
54 else:
55 result = sympy.integrate(ex, (v, a._sympy_(), b._sympy_()))
---> 56 return result._sage_()
57
58 def mma_free_integrator(expression, v, a=None, b=None):
/usr/lib/python2.7/site-packages/sage/interfaces/sympy.py in _sympysage_piecewise(self)
508 """
509 from sage.functions.other import cases
--> 510 return cases([(p.cond._sage_(),p.expr._sage_()) for p in self.args])
511
512 def _sympysage_fresnels(self):
/usr/lib/python2.7/site-packages/sage/interfaces/sympy.py in _sympysage_add(self)
190 s = 0
191 for x in self.args:
--> 192 s += x._sage_()
193 return s
194
/usr/lib/python2.7/site-packages/sage/interfaces/sympy.py in _sympysage_mul(self)
204 s = 1
205 for x in self.args:
--> 206 s *= x._sage_()
207 return s
208
/usr/lib/python2.7/site-packages/sage/interfaces/sympy.py in _sympysage_function(self)
273 fname = self.func.__name__
274 func = getattr(sagefuncs, fname, None)
--> 275 args = [arg._sage_() for arg in self.args]
276
277 # In the case the function is not known in sage:
AttributeError: 'TupleArg' object has no attribute '_sage_'
sage:
Sagemath seems to ship with its own python and sympy. So may be this is an older sympy it is using? I have python 3.6.5 installed on my Linux, and it works ok there, with sympy 1.1.1
[me@me-pc rubi_4_15_2]$ python --version
Python 3.6.5 :: Anaconda, Inc.
[me@me-pc rubi_4_15_2]$ python
Python 3.6.5 |Anaconda, Inc.| (default, Apr 29 2018, 16:14:56)
[GCC 7.2.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> from sympy import *
>>> t=symbols('t')
>>> integrate(log(t)/(t + 1),t)
Piecewise((I*pi*log(t + 1) - polylog(2, t + 1), Abs(t + 1) < 1), (-I*pi*log(1/(t + 1)) - polylog(2, t + 1), Abs(1/(t + 1)) < 1), (-I*pi*meijerg(((), (1, 1)), ((0, 0), ()), t + 1) + I*pi*meijerg(((1, 1), ()), ((), (0, 0)), t + 1) - polylog(2, t + 1), True))
>>>
