Still wrestling with dsolve... Below is a call with an arbitrary
differential equation. Any idea why dsolve is returning terms with these
enormous integers? All of the coefficients are floats in this case. The
expression is impervious to .n() (as mentioned in my earlier question).
Converting to a numpy function to evaluate the results works, but throws
an exception when called.
I can't seem to get past this point in the analysis. Any idea how I can
get this into a form I can continue working with?
A=symbols(r'A',cls=Function)
t=symbols(r't')
Eq4=-123456.78*A(t)-9876.54*A(t).diff(t)-0.00032*A(t).diff(t,2)+1357908.64
soln=dsolve(Eq4)
print(soln.n())
A(t) == C1*exp(125*t*(-33935533038108675 -
sqrt(1151618536954453541512853661417481))/274877906944) +
C2*exp(125*t*(-33935533038108675 +
sqrt(1151618536954453541512853661417481))/274877906944) + 10.999060885923
fn=lambdify(t,soln.rhs,'numpy')
fn(3.2)
---------------------------------------------------------------------------AttributeError
Traceback (most recent call
last)<ipython-input-42-bde0572cbbe1> in <module>()----> 1 fn(3.2)
//anaconda/lib/python3.4/site-packages/numpy/__init__.py in <lambda>(_Dummy_73)
AttributeError: 'int' object has no attribute 'sqrt'
--
You received this message because you are subscribed to the Google Groups
"sympy" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To post to this group, send email to [email protected].
Visit this group at http://groups.google.com/group/sympy.
To view this discussion on the web visit
https://groups.google.com/d/msgid/sympy/88a9432e-a322-460b-9556-ddd85cdad519%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
