core: removed Expr.lseries()

diofant/core/expr.py

@@ -2483,29 +2483,6 @@ def taylor_term(self, n, x, *previous_terms):
         _x = Dummy('x')
         return self.subs({x: _x}).diff((_x, n)).subs({_x: x}).subs({x: 0}) * x**n / factorial(n)
 
-    def lseries(self, x=None, x0=0, dir='+', logx=None):
-        """Wrapper for series yielding an iterator of the terms of the series.
-
-        Note: an infinite series will yield an infinite iterator. The following,
-        for exaxmple, will never terminate. It will just keep printing terms
-        of the sin(x) series::
-
-          for term in sin(x).lseries(x):
-              print term
-
-        The advantage of lseries() over nseries() is that many times you are
-        just interested in the next term in the series (i.e. the first term for
-        example), but you don't know how many you should ask for in nseries()
-        using the "n" parameter.
-
-        See Also
-        ========
-
-        nseries
-
-        """
-        return self.series(x, x0, n=None, dir=dir, logx=logx)
-
     def _eval_lseries(self, x, logx=None):
         # default implementation of lseries is using nseries(), and adaptively
         # increasing the "n". As you can see, it is not very efficient, because
@@ -2564,7 +2541,6 @@ def nseries(self, x, n=6, logx=None):
         ========
 
         series
-        lseries
 
         Examples
         ========
@@ -2735,7 +2711,7 @@ def compute_leading_term(self, x, logx=None):
 
         d = logx if logx else Dummy('logx')
 
-        for t in self.lseries(x, logx=d):
+        for t in self.series(x, n=None, logx=d):
             t = t.cancel()
 
             is_zero = t.equals(0)

diofant/core/function.py

@@ -1232,7 +1232,7 @@ def _subset(a, b):
         return Derivative(*(x._subs(old, new) for x in self.args))
 
     def _eval_lseries(self, x, logx):
-        for term in self.expr.lseries(x, logx=logx):
+        for term in self.expr.series(x, n=None, logx=logx):
             yield self.func(term, *self.variables)
 
     def _eval_nseries(self, x, n, logx):

diofant/integrals/integrals.py

@@ -916,7 +916,7 @@ def _eval_lseries(self, x, logx):
             if x in l[1:]:
                 symb = l[0]
                 break
-        for term in expr.function.lseries(symb, logx):
+        for term in expr.function.series(symb, n=None, logx=logx):
             yield integrate(term, *expr.limits)
 
     def _eval_nseries(self, x, n, logx):

diofant/tests/integrals/test_integrals.py

@@ -865,7 +865,7 @@ def test_is_real():
 
 def test_series():
     i = Integral(cos(x), (x, x))
-    e = i.lseries(x)
+    e = i.series(x, n=None)
     s1 = i.nseries(x, n=8).removeO().doit()
     s2 = Add(*[next(e) for j in range(4)])
     assert s1 == s2

diofant/tests/series/test_lseries.py

@@ -6,51 +6,51 @@
 
 
 def test_sin():
-    e = sin(x).lseries(x)
+    e = sin(x).series(x, n=None)
     assert next(e) == x
     assert next(e) == -x**3/6
     assert next(e) == x**5/120
 
 
 def test_cos():
-    e = cos(x).lseries(x)
+    e = cos(x).series(x, n=None)
     assert next(e) == 1
     assert next(e) == -x**2/2
     assert next(e) == x**4/24
 
 
 def test_exp():
-    e = exp(x).lseries(x)
+    e = exp(x).series(x, n=None)
     assert next(e) == 1
     assert next(e) == x
     assert next(e) == x**2/2
     assert next(e) == x**3/6
 
 
 def test_exp2():
-    e = exp(cos(x)).lseries(x)
+    e = exp(cos(x)).series(x, n=None)
     assert next(e) == E
     assert next(e) == -E*x**2/2
     assert next(e) == E*x**4/6
     assert next(e) == -31*E*x**6/720
 
 
 def test_simple():
-    assert list(x.lseries()) == [x]
-    assert list(Integer(1).lseries(x)) == [1]
-    assert not next((x/(x + y)).lseries(y)).has(O)
-    assert [t.doit() for t in Derivative(1 + x, x).lseries(x)] == [0, 1]
+    assert list(x.series(n=None)) == [x]
+    assert list(Integer(1).series(x, n=None)) == [1]
+    assert not next((x/(x + y)).series(y, n=None)).has(O)
+    assert [t.doit() for t in Derivative(1 + x, x).series(x, n=None)] == [0, 1]
 
     # issue sympy/sympy#5183
-    s = (x + 1/x).lseries()
+    s = (x + 1/x).series(n=None)
     assert list(s) == [1/x, x]
 
 
 def test_sympyissue_5183():
-    s = (x + 1/x).lseries()
-    assert next((x + x**2).lseries()) == x
-    assert next(((1 + x)**7).lseries(x)) == 1
-    assert next((sin(x + y)).series(x, n=3).lseries(y)) == x
+    s = (x + 1/x).series(n=None)
+    assert next((x + x**2).series(n=None)) == x
+    assert next(((1 + x)**7).series(x, n=None)) == 1
+    assert next((sin(x + y)).series(x, n=3).series(y, n=None)) == x
     # it would be nice if all terms were grouped, but in the
     # following case that would mean that all the terms would have
     # to be known since, for example, every term has a constant in it.
@@ -60,7 +60,7 @@ def test_sympyissue_5183():
 
 def test_tanh():
     # issue sympy/sympy#6999
-    s = tanh(x).lseries(x, 1)
+    s = tanh(x).series(x, x0=1, n=None)
     assert next(s) == tanh(1)
     assert next(s) == x - (x - 1)*tanh(1)**2 - 1
     assert next(s) == -(x - 1)**2*tanh(1) + (x - 1)**2*tanh(1)**3

diofant/tests/series/test_series.py

@@ -65,7 +65,7 @@ def test_simple():
 
 
 def test_sympyissue_5223():
-    assert next(Integer(0).lseries(x)) == 0
+    assert next(Integer(0).series(x, n=None)) == 0
     assert cos(x).series() == cos(x).series(x)
 
     e = cos(x).series(x, 1, n=None)
@@ -78,7 +78,7 @@ def test_sympyissue_5223():
         E - E*(-x + 1) + E*(-x + 1)**2/2
 
     D = Derivative
-    assert next(D(cos(x), x).lseries()) == D(1, x)
+    assert next(D(cos(x), x).series(n=None)) == D(1, x)
     assert D(exp(x), x).series(n=3) == (D(1, x) + D(x, x) + D(x**2/2, x) +
                                         D(x**3/6, x) + O(x**3))
 

docs/release/notes-0.13.rst

@@ -24,6 +24,7 @@ Compatibility breaks
 * Removed ``igcd()``, ``ilcm()`` and ``prod()`` functions, see :pull:`1125`.
 * Changed the :class:`~diofant.core.function.Derivative` (and similary :func:`~diofant.core.function.diff`) syntax to ``Derivative(foo, (x, 2))`` from ``Derivative(foo, x, 2)``, see :pull:`1131`.
 * Removed ``prem()`` function, see :pull:`1140`.
+* Removed ``lseries()`` method of :class:`~diofant.core.expr.Expr`, use :meth:`~diofant.core.expr.Expr.series` with ``n=None``, see :pull:`1146`.
 
 Minor changes
 =============