This seems to be a rather serious bug, the ordering returned by tsolve() is not reproducible, you always get the Lambert term before the log. This makes comparison impossible.
Anyway, I sent a patch at least fixing the test. Vinzent On 2 Dez., 17:15, Vinzent Steinberg <[email protected]> wrote: > Well, either upgrading to Python 2.7.1 or running ./setup.py clean did > help (However, I used py.cleanup before reporting any of this. And I > was able reproduce it with a clean clone.). Now I get a much nicer > failure: > > executable: /usr/bin/python2 (2.7.1-final-0) > > sympy/solvers/tests/ > test_solvers.py[18] ..............F... [FAIL] > > ___________________________________________________________________________ > _____ > ______________ sympy/solvers/tests/test_solvers.py:test_tsolve_1 > _______________ > File "/home/one/src/sympy/sympy/solvers/tests/test_solvers.py", line > 232, in test_tsolve_1 > [-((4*log(7) + > 5*LambertW(-7*2**Rational(4,5)*6**Rational(1,5)*log(7)/10))/ > (3*log(7)))]] > AssertionError > > ============= tests finished: 17 passed, 1 failed, in 2.82 seconds > ============= > DO *NOT* COMMIT! > > In isympy: > > In [1]: solve(2*(3*x+4)**5 - 6*7**(3*x+9), x) > Out[1]: > ⎡ ⎛ ⎛ 5 ⎽⎽⎽ ⎞⎞⎤ > ⎢ ⎜ ⎜-7⋅╲╱ 3 ⋅log(7)⎟⎟⎥ > ⎢-⎜4⋅log(7) + 5⋅LambertW⎜───────────────⎟⎟⎥ > ⎢ ⎝ ⎝ 5 ⎠⎠⎥ > ⎢─────────────────────────────────────────⎥ > ⎣ 3⋅log(7) ⎦ > > In [2]: _[0].evalf() > Out[2]: -1.8108123000607 - 1.59457436286436⋅ⅈ > > In [3]: nsolve(2*(3*x+4)**5 - 6*7**(3*x+9), x, -1.8 - 1.6j) > Out[3]: (-1.8108123000607 - 1.59457436286436j) > > This is due to this strange inconsistency (due to hashing): > > In [1]: s = solve(2*(3*x+4)**5 - 6*7**(3*x+9), x) > > In [2]: s > Out[2]: > ⎡ ⎛ ⎛ 5 ⎽⎽⎽ ⎞⎞⎤ > ⎢ ⎜ ⎜-7⋅╲╱ 3 ⋅log(7)⎟⎟⎥ > ⎢-⎜4⋅log(7) + 5⋅LambertW⎜───────────────⎟⎟⎥ > ⎢ ⎝ ⎝ 5 ⎠⎠⎥ > ⎢─────────────────────────────────────────⎥ > ⎣ 3⋅log(7) ⎦ > > In [3]: sstr(s) > Out[3]: [-(4*log(7) + 5*LambertW(-7*3**(1/5)*log(7)/5))/(3*log(7))] > > In [4]: [-(4*log(7) + 5*LambertW(-7*3**(S(1)/5)*log(7)/5))/(3*log(7))] > Out[4]: > ⎡ ⎛ 5 ⎽⎽⎽ ⎞ ⎤ > ⎢ ⎜-7⋅╲╱ 3 ⋅log(7)⎟ ⎥ > ⎢- 5⋅LambertW⎜───────────────⎟ - 4⋅log(7)⎥ > ⎢ ⎝ 5 ⎠ ⎥ > ⎢────────────────────────────────────────⎥ > ⎣ 3⋅log(7) ⎦ > > I'm working on a patch. > > Vinzent -- You received this message because you are subscribed to the Google Groups "sympy" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
