sympy/sympy — pull request #990 by hunteke (2012-01-16 07:35:51+00:00)
Title: GreaterThan/LessThan refactor

Hullo SymPy Devs,

I've a branch that replaces Inequality with GreaterThan/LessThan. In short, this means that equations with >(=) no longer get converted to LessThan relations:

>>> x > y
x > y
>>> simpify(2) > x
2 > x

It currently passes all doctests and all but 3 tests. However, I need some help with those, and I'm not entirely sure they aren't incorrect tests to begin with. The specific tests that fail:

* test_autowrap [130]: test_wrap_twice_c_cython
This also fails for me on the master branch where I've done nothing.

* test_transforms [281]: test_expint
I do not know how to verify if this is (in)correct. (In multiple lines here for clarity.)

``` python
assert inverse_laplace_transform((s - log(s + 1))/s**2, s, x)
.rewrite(expint).expand()
==
(expint(2, x)*Heaviside(x)).rewrite(Ei).rewrite(expint).expand()
```

* test_transforms [465]: test_inverse_laplace_transform
I similarly do not have the context to verify if it's correct.
assert ILT(1/s, s, t) == Heaviside(t)

Thanks for your help,

Kevin