Merge branch 'copy_variable_data' into 'master'

Copy variable data

See merge request integer/scip!3375

CHANGELOG

@@ -4,6 +4,7 @@
 Features
 --------
 - Added new fields in history to store ancestral pseudo cost updates, used in the pseudo costs branching rule to compute discounted pseudo costs.
+- Copy variable data pointer if no copy routine was supplied.
 
 Performance improvements
 ------------------------

src/scip/type_var.h

@@ -135,8 +135,8 @@ typedef struct SCIP_VarData SCIP_VARDATA;         /**< user variable data */
  *  Because the original variable and the user data of the original variable should not be
  *  modified during the solving process, a transformed variable is created as a copy of
  *  the original variable. If the user variable data is never modified during the solving
- *  process anyways, it is enough to simple copy the user data's pointer. This is the
- *  default implementation, which is used when a NULL is given as VARTRANS method.
+ *  process anyways, it is enough to simply copy the user data's pointer. This is the
+ *  default implementation, which is used when NULL is given as the VARTRANS method.
  *  If the user data may be modified during the solving process (e.g. during preprocessing),
  *  the VARTRANS method must be given and has to copy the user variable data to a different
  *  memory location.
@@ -166,13 +166,13 @@ typedef struct SCIP_VarData SCIP_VARDATA;         /**< user variable data */
 /** copies variable data of source SCIP variable for the target SCIP variable
  *
  *  This method should copy the variable data of the source SCIP and create a target variable data for target
- *  variable. This callback is optimal. If the copying process was successful the target variable gets this variable
- *  data assigned. In case the result pointer is set to SCIP_DIDNOTRUN the target variable will have no variable data at
+ *  variable. This callback is optional. If the copying process was successful, the target variable gets this variable
+ *  data assigned. In case the result pointer is set to SCIP_DIDNOTRUN, the target variable will have no variable data at
  *  all.
  *
  *  The variable map and the constraint map can be used via the function SCIPgetVarCopy() and SCIPgetConsCopy(),
  *  respectively, to get for certain variables and constraints of the source SCIP the counter parts in the target
- *  SCIP. You should be very carefully in using these two methods since they could lead to infinity loop.
+ *  SCIP. You should be very careful in using these two methods since they could lead to infinite loop.
  *
  *  input:
  *  - scip            : target SCIP data structure

src/scip/var.c

@@ -2219,28 +2219,36 @@ SCIP_RETCODE SCIPvarCopy(
    SCIP_CALL( SCIPhashmapInsert(varmap, sourcevar, *var) );
 
    /* in case there exists variable data and the variable data copy callback, try to copy variable data */
-   if( sourcevar->vardata != NULL && sourcevar->varcopy != NULL )
+   if( sourcevar->vardata != NULL )
    {
-      SCIP_CALL( sourcevar->varcopy(set->scip, sourcescip, sourcevar, sourcevar->vardata, 
-            varmap, consmap, (*var), &targetdata, &result) );
-
-      /* evaluate result */
-      if( result != SCIP_DIDNOTRUN && result != SCIP_SUCCESS )
+      if( sourcevar->varcopy != NULL )
       {
-         SCIPerrorMessage("variable data copying method returned invalid result <%d>\n", result);
-         return SCIP_INVALIDRESULT;
-      }
+         SCIP_CALL( sourcevar->varcopy(set->scip, sourcescip, sourcevar, sourcevar->vardata,
+               varmap, consmap, (*var), &targetdata, &result) );
+
+         /* evaluate result */
+         if( result != SCIP_DIDNOTRUN && result != SCIP_SUCCESS )
+         {
+            SCIPerrorMessage("variable data copying method returned invalid result <%d>\n", result);
+            return SCIP_INVALIDRESULT;
+         }
 
-      assert(targetdata == NULL || result == SCIP_SUCCESS);
+         assert(targetdata == NULL || result == SCIP_SUCCESS);
 
-      /* if copying was successful, add the created variable data to the variable as well as all callback methods */
-      if( result == SCIP_SUCCESS )
+         /* if copying was successful, add the created variable data to the variable as well as all callback methods */
+         if( result == SCIP_SUCCESS )
+         {
+            (*var)->varcopy = sourcevar->varcopy;
+            (*var)->vardelorig = sourcevar->vardelorig;
+            (*var)->vartrans = sourcevar->vartrans;
+            (*var)->vardeltrans = sourcevar->vardeltrans;
+            (*var)->vardata = targetdata;
+         }
+      }
+      else
       {
-         (*var)->varcopy = sourcevar->varcopy;
-         (*var)->vardelorig = sourcevar->vardelorig;
-         (*var)->vartrans = sourcevar->vartrans;
-         (*var)->vardeltrans = sourcevar->vardeltrans;
-         (*var)->vardata = targetdata;
+         /* if there is no copy callback, just copy data pointers */
+         (*var)->vardata = sourcevar->vardata;
       }
    }