X-Git-Url: https://scm.cri.ensmp.fr/git/linpy.git/blobdiff_plain/950e4adf4d155a2880fbfcd61021f775dfddaeac..b2931230a184025bdb6006bfe48c9b1dc18dc351:/linpy/linexprs.py

diff --git a/linpy/linexprs.py b/linpy/linexprs.py
index 961502d..eff4a7e 100644
--- a/linpy/linexprs.py
+++ b/linpy/linexprs.py
@@ -62,7 +62,7 @@ class LinExpr:
         symbols to their coefficients, and a constant term. The coefficients and
         the constant term must be rational numbers.
 
-        For example, the linear expression x + 2y + 1 can be constructed using
+        For example, the linear expression x + 2*y + 1 can be constructed using
         one of the following instructions:
 
         >>> x, y = symbols('x y')
@@ -76,7 +76,7 @@ class LinExpr:
 
         Alternatively, linear expressions can be constructed from a string:
 
-        >>> LinExpr('x + 2*y + 1')
+        >>> LinExpr('x + 2y + 1')
 
         A linear expression with a single symbol of coefficient 1 and no
         constant term is automatically subclassed as a Symbol instance. A linear
@@ -245,28 +245,34 @@ class LinExpr:
     @_polymorphic
     def __eq__(self, other):
         """
-        Test whether two linear expressions are equal.
+        Test whether two linear expressions are equal. Unlike methods
+        LinExpr.__lt__(), LinExpr.__le__(), LinExpr.__ge__(), LinExpr.__gt__(),
+        the result is a boolean value, not a polyhedron. To express that two
+        linear expressions are equal or not equal, use functions Eq() and Ne()
+        instead.
         """
-        if isinstance(other, LinExpr):
-            return self._coefficients == other._coefficients and \
-                self._constant == other._constant
-        return NotImplemented
-
-    def __le__(self, other):
-        from .polyhedra import Le
-        return Le(self, other)
+        return self._coefficients == other._coefficients and \
+            self._constant == other._constant
 
+    @_polymorphic
     def __lt__(self, other):
-        from .polyhedra import Lt
-        return Lt(self, other)
+        from .polyhedra import Polyhedron
+        return Polyhedron([], [other - self - 1])
 
+    @_polymorphic
+    def __le__(self, other):
+        from .polyhedra import Polyhedron
+        return Polyhedron([], [other - self])
+
+    @_polymorphic
     def __ge__(self, other):
-        from .polyhedra import Ge
-        return Ge(self, other)
+        from .polyhedra import Polyhedron
+        return Polyhedron([], [self - other])
 
+    @_polymorphic
     def __gt__(self, other):
-        from .polyhedra import Gt
-        return Gt(self, other)
+        from .polyhedra import Polyhedron
+        return Polyhedron([], [self - other - 1])
 
     def scaleint(self):
         """