Merge branch 't/20303/fixes_for_the_cvxopt_mip_backend' into t/20354/…

…pplbackend__add_support_for_integer_variables
sagemath · Apr 5, 2016 · b0179c2 · b0179c2
2 parents 9f35b65 + e47b608
commit b0179c2
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Showing 6 changed files with 103 additions and 15 deletions.
diff --git a/src/sage/numerical/backends/coin_backend.pyx b/src/sage/numerical/backends/coin_backend.pyx
@@ -179,10 +179,21 @@ cdef class CoinBackend(GenericBackend):
             4
             sage: p.ncols()                                                # optional - cbc
             5
-            sage: p.add_variables(2, lower_bound=-2.0, integer=True, names=['a','b']) # optional - cbc
+            sage: p.add_variables(2, lower_bound=-2.0, integer=True, obj=42.0, names=['a','b']) # optional - cbc
             6
-            sage: p.col_name(5)                                                        # optional - cbc
+
+        TESTS:
+
+        Check that arguments are used::
+
+            sage: p.col_bounds(5) # tol 1e-8, optional - cbc
+            (-2.0, None)
+            sage: p.is_variable_integer(5)   # optional - cbc
+            True
+            sage: p.col_name(5)              # optional - cbc
             'a'
+            sage: p.objective_coefficient(5) # tol 1e-8, optional - cbc
+            42.0
         """
         #cdef int vtype = int(bool(binary)) + int(bool(continuous)) + int(bool(integer))
         cdef int vtype = int(binary) + int(continuous) + int(integer)
@@ -1685,4 +1696,4 @@ cdef class CoinBackend(GenericBackend):
             raise MIPSolverException('CBC : Signal sent, getReducedCost() fails')
         else:
             cost = [c_cost[i] for i in range(n)]
-            return cost
+            return cost
diff --git a/src/sage/numerical/backends/cplex_backend.pyx b/src/sage/numerical/backends/cplex_backend.pyx
@@ -170,8 +170,21 @@ cdef class CPLEXBackend(GenericBackend):
             4
             sage: p.ncols()                                                # optional - CPLEX
             5
-            sage: p.add_variables(2, lower_bound=-2.0, integer=True, names=['a','b']) # optional - CPLEX
+            sage: p.add_variables(2, lower_bound=-2.0, integer=True, obj=42.0, names=['a','b']) # optional - CPLEX
             6
+
+        TESTS:
+
+        Check that arguments are used::
+
+            sage: p.col_bounds(5) # tol 1e-8, optional - CPLEX
+            (-2.0, None)
+            sage: p.is_variable_integer(5)   # optional - CPLEX
+            True
+            sage: p.col_name(5)              # optional - CPLEX
+            'a'
+            sage: p.objective_coefficient(5) # tol 1e-8, optional - CPLEX
+            42.0
         """
         cdef char * c_name
         cdef double c_coeff = obj

diff --git a/src/sage/numerical/backends/cvxopt_backend.pyx b/src/sage/numerical/backends/cvxopt_backend.pyx
@@ -138,7 +138,7 @@ cdef class CVXOPTBackend(GenericBackend):
             ...
             RuntimeError: CVXOPT only supports continuous variables
         """
-        if obj == None:
+        if obj is None:
             obj = 0.0
         if binary or integer:
             raise RuntimeError("CVXOPT only supports continuous variables")
@@ -150,7 +150,7 @@ cdef class CVXOPTBackend(GenericBackend):
         return len(self.objective_function) - 1
 
 
-    cpdef int add_variables(self, int n, lower_bound=None, upper_bound=None, binary=False, continuous=True, integer=False, obj=None, names=None) except -1:
+    cpdef int add_variables(self, int n, lower_bound=0.0, upper_bound=None, binary=False, continuous=True, integer=False, obj=None, names=None) except -1:
         """
         Add ``n`` variables.
 
@@ -187,11 +187,23 @@ cdef class CVXOPTBackend(GenericBackend):
             4
             sage: p.ncols()
             5
-            sage: p.add_variables(2, lower_bound=-2.0, integer=True, names=['a','b'])
+            sage: p.add_variables(2, lower_bound=-2.0, obj=42.0, names=['a','b'])
             6
+
+        TESTS:
+
+        Check that arguments are used::
+
+            sage: p.col_bounds(5) # tol 1e-8
+            (-2.0, None)
+            sage: p.col_name(5)
+            'a'
+            sage: p.objective_coefficient(5) # tol 1e-8
+            42.0
         """
         for i in range(n):
-            self.add_variable()
+            self.add_variable(lower_bound, upper_bound, binary, continuous, integer, obj,
+                              None if names is None else names[i])
         return len(self.objective_function) - 1;
 
 
@@ -417,10 +429,17 @@ cdef class CVXOPTBackend(GenericBackend):
             ([], [])
             sage: p.row_bounds(4)
             (None, 2)
+
+        TESTS:
+
+        It does not add mysterious new variables::
+
+            sage: p.ncols()
+            5
+
         """
         for i in range(number):
-            self.add_linear_constraint(zip(range(self.ncols()+1),[0]*(self.ncols()+1)), 
-                                       lower_bound, upper_bound, 
+            self.add_linear_constraint([], lower_bound, upper_bound,
                                        name=None if names is None else names[i])
 
     cpdef int solve(self) except -1:
@@ -1022,7 +1041,7 @@ cdef class CVXOPTBackend(GenericBackend):
             sage: p.solver_parameter("show_progress")
             True
         """
-        if value == None:
+        if value is None:
             return self.param[name]
         else:
             self.param[name] = value

diff --git a/src/sage/numerical/backends/glpk_backend.pyx b/src/sage/numerical/backends/glpk_backend.pyx
@@ -176,8 +176,21 @@ cdef class GLPKBackend(GenericBackend):
             4
             sage: p.ncols()
             5
-            sage: p.add_variables(2, lower_bound=-2.0, integer=True, names=['a','b'])
+            sage: p.add_variables(2, lower_bound=-2.0, integer=True, obj=42.0, names=['a','b'])
             6
+
+        TESTS:
+
+        Check that arguments are used::
+
+            sage: p.col_bounds(5) # tol 1e-8
+            (-2.0, None)
+            sage: p.is_variable_integer(5)
+            True
+            sage: p.col_name(5)
+            'a'
+            sage: p.objective_coefficient(5)
+            42.0
         """
         cdef int vtype = int(bool(binary)) + int(bool(continuous)) + int(bool(integer))
         if  vtype == 0:
@@ -206,7 +219,7 @@ cdef class GLPKBackend(GenericBackend):
                 self.objective_coefficient(n_var - i - 1, obj)
 
             if names is not None:
-                glp_set_col_name(self.lp, n_var, names[number - i - 1])
+                glp_set_col_name(self.lp, n_var - i, names[number - i - 1])
 
         return n_var - 1
 

diff --git a/src/sage/numerical/backends/gurobi_backend.pyx b/src/sage/numerical/backends/gurobi_backend.pyx
@@ -196,8 +196,21 @@ cdef class GurobiBackend(GenericBackend):
             4
             sage: p.ncols()                                                                # optional - Gurobi
             5
-            sage: p.add_variables(2, lower_bound=-2.0, integer=True, names=['a','b'])      # optional - Gurobi
+            sage: p.add_variables(2, lower_bound=-2.0, integer=True, obj=42.0, names=['a','b']) # optional - Gurobi
             6
+
+        TESTS:
+
+        Check that arguments are used::
+
+            sage: p.col_bounds(5) # tol 1e-8, optional - Gurobi
+            (-2.0, None)
+            sage: p.is_variable_integer(5)   # optional - Gurobi
+            True
+            sage: p.col_name(5)              # optional - Gurobi
+            'a'
+            sage: p.objective_coefficient(5) # tol 1e-8, optional - Gurobi
+            42.0
         """
         cdef int i
         cdef int value

diff --git a/src/sage/numerical/backends/ppl_backend.pyx b/src/sage/numerical/backends/ppl_backend.pyx
@@ -178,7 +178,13 @@ cdef class PPLBackend(GenericBackend):
             'x'
             sage: p.objective_coefficient(2)
             2/3
+            sage: p.add_variable(integer=True)
+            Traceback (most recent call last):
+            ...
+            NotImplementedError: The PPL backend in Sage only supports continuous variables
         """
+        if binary or integer:
+            raise NotImplementedError("The PPL backend in Sage only supports continuous variables")
         for i in range(len(self.Matrix)):
             self.Matrix[i].append(0)
         self.col_lower_bound.append(lower_bound)
@@ -226,9 +232,22 @@ cdef class PPLBackend(GenericBackend):
             4
             sage: p.ncols()
             5
-            sage: p.add_variables(2, lower_bound=-2.0, names=['a','b'])
+            sage: p.add_variables(2, lower_bound=-2.0, obj=42.0, names=['a','b'])
             6
+
+        TESTS:
+
+        Check that arguments are used::
+
+            sage: p.col_bounds(5) # tol 1e-8
+            (-2.0, None)
+            sage: p.col_name(5)
+            'a'
+            sage: p.objective_coefficient(5) # tol 1e-8
+            42.0
         """
+        if binary or integer:
+            raise NotImplementedError("The PPL backend in Sage only supports continuous variables")
         for k in range(n):
             for i in range(len(self.Matrix)):
                 self.Matrix[i].append(0)