Changeset 2328:b4931ae52069 in lemon-0.x for lemon/lp_base.h

Timestamp:

12/07/06 17:10:54 (17 years ago)

Author:

athos

Branch:

default

Phase:

public

Convert:

svn:c9d7d8f5-90d6-0310-b91f-818b3a526b0e/lemon/trunk@3104

Message:

Query functions have been implemented for GLPK (CPLEX breaks at the moment, I guess): These functions include:
retrieving one element of the coeff. matrix
retrieving one element of the obj function
lower bd for a variable
upper bound for a variable
lower and upper bounds for a row (these can not be handled separately at the moment)
direction of the optimization (is_max() function)

File:

• lemon/lp_base.h (modified) (4 diffs)

lemon/lp_base.h

@@ -707 +707 @@
 
     virtual void _setColLowerBound(int i, Value value) = 0;
+    virtual Value _getColLowerBound(int i) = 0;
     virtual void _setColUpperBound(int i, Value value) = 0;
+    virtual Value _getColUpperBound(int i) = 0;
 //     virtual void _setRowLowerBound(int i, Value value) = 0;
 //     virtual void _setRowUpperBound(int i, Value value) = 0;
     virtual void _setRowBounds(int i, Value lower, Value upper) = 0;
+    virtual void _getRowBounds(int i, Value &lower, Value &upper)=0;
+
     virtual void _setObjCoeff(int i, Value obj_coef) = 0;
     virtual Value _getObjCoeff(int i) = 0;
@@ -1025 +1029 @@
       _setColLowerBound(_lpId(c),value);
     }
+
+    /// Get the lower bound of a column (i.e a variable)
+
+    /// This function returns the lower bound for column (variable) \t c
+    /// (this might be -\ref INF as well).  
+    ///\return The lower bound for coloumn \t c
+    Value colLowerBound(Col c) {
+      return _getColLowerBound(_lpId(c));
+    }
     
     ///\brief Set the lower bound of  several columns
@@ -1072 +1085 @@
     };
 
-    ///\brief Set the lower bound of  several columns
+    /// Get the upper bound of a column (i.e a variable)
+
+    /// This function returns the upper bound for column (variable) \t c
+    /// (this might be \ref INF as well).  
+    ///\return The upper bound for coloumn \t c
+    Value colUpperBound(Col c) {
+      return _getColUpperBound(_lpId(c));
+    }
+
+    ///\brief Set the upper bound of  several columns
     ///(i.e a variables) at once
     ///
@@ -1177 +1199 @@
     /// Set the lower and the upper bounds of a row (i.e a constraint)
 
-    /// The lower and the upper bounds of
+    /// The lower and the upper bound of
     /// a constraint (row) have to be given by an 
     /// extended number of type Value, i.e. a finite number of type 
-    /// Value, -\ref INF or \ref INF.
+    /// Value, -\ref INF or \ref INF. There is no separate function for the 
+    /// lower and the upper bound because that would have been hard to implement 
+    /// for CPLEX.
     void rowBounds(Row c, Value lower, Value upper) {
       _setRowBounds(_lpId(c),lower, upper);
-      // _setRowUpperBound(_lpId(c),upper);
-    }
-    
+    }
+    
+    /// Get the lower and the upper bounds of a row (i.e a constraint)
+
+    /// The lower and the upper bound of
+    /// a constraint (row) are  
+    /// extended numbers of type Value, i.e.  finite numbers of type 
+    /// Value, -\ref INF or \ref INF. 
+    /// \todo There is no separate function for the 
+    /// lower and the upper bound because we had problems with the 
+    /// implementation of the setting functions for CPLEX:  
+    /// check out whether this can be done for these functions.
+    void getRowBounds(Row c, Value &lower, Value &upper) {
+      _getRowBounds(_lpId(c),lower, upper);
+    }
+
     ///Set an element of the objective function
     void objCoeff(Col c, Value v) {_setObjCoeff(_lpId(c),v); };