Deprecate set group (#4864)

* Convert jvm package and R package.

* Restore for compatibility.

R-package/src/xgboost_R.cc

@@ -166,7 +166,9 @@ SEXP XGDMatrixSetInfo_R(SEXP handle, SEXP field, SEXP array) {
     for (int i = 0; i < len; ++i) {
       vec[i] = static_cast<unsigned>(INTEGER(array)[i]);
     }
-    CHECK_CALL(XGDMatrixSetGroup(R_ExternalPtrAddr(handle), BeginPtr(vec), len));
+    CHECK_CALL(XGDMatrixSetUIntInfo(R_ExternalPtrAddr(handle),
+                                    CHAR(asChar(field)),
+                                    BeginPtr(vec), len));
   } else {
     std::vector<float> vec(len);
     #pragma omp parallel for schedule(static)
@@ -174,8 +176,8 @@ SEXP XGDMatrixSetInfo_R(SEXP handle, SEXP field, SEXP array) {
       vec[i] = REAL(array)[i];
     }
     CHECK_CALL(XGDMatrixSetFloatInfo(R_ExternalPtrAddr(handle),
-                                   CHAR(asChar(field)),
+                                     CHAR(asChar(field)),
-                                   BeginPtr(vec), len));
+                                     BeginPtr(vec), len));
   }
   R_API_END();
   return R_NilValue;

include/xgboost/c_api.h

@@ -273,8 +273,9 @@ XGB_DLL int XGDMatrixSetUIntInfo(DMatrixHandle handle,
                                  const char *field,
                                  const unsigned *array,
                                  bst_ulong len);
+
 /*!
- * \brief set label of the training matrix
+ * \brief (deprecated) Use XGDMatrixSetUIntInfo instead. Set group of the training matrix
  * \param handle a instance of data matrix
  * \param group pointer to group size
  * \param len length of array
@@ -283,8 +284,9 @@ XGB_DLL int XGDMatrixSetUIntInfo(DMatrixHandle handle,
 XGB_DLL int XGDMatrixSetGroup(DMatrixHandle handle,
                               const unsigned *group,
                               bst_ulong len);
+
 /*!
- * \brief get float info vector from matrix
+ * \brief get float info vector from matrix.
  * \param handle a instance of data matrix
  * \param field field name
  * \param out_len used to set result length

jvm-packages/xgboost4j/src/main/java/ml/dmlc/xgboost4j/java/DMatrix.java

@@ -201,7 +201,7 @@ public class DMatrix {
    * @throws XGBoostError native error
    */
   public void setGroup(int[] group) throws XGBoostError {
-    XGBoostJNI.checkCall(XGBoostJNI.XGDMatrixSetGroup(handle, group));
+    XGBoostJNI.checkCall(XGBoostJNI.XGDMatrixSetUIntInfo(handle, "group", group));
   }
 
   /**

jvm-packages/xgboost4j/src/main/java/ml/dmlc/xgboost4j/java/XGBoostJNI.java

@@ -75,8 +75,6 @@ class XGBoostJNI {
 
   public final static native int XGDMatrixSetUIntInfo(long handle, String field, int[] array);
 
-  public final static native int XGDMatrixSetGroup(long handle, int[] group);
-
   public final static native int XGDMatrixGetFloatInfo(long handle, String field, float[][] info);
 
   public final static native int XGDMatrixGetUIntInfo(long handle, String filed, int[][] info);

jvm-packages/xgboost4j/src/native/xgboost4j.cpp

@@ -352,22 +352,6 @@ JNIEXPORT jint JNICALL Java_ml_dmlc_xgboost4j_java_XGBoostJNI_XGDMatrixSetUIntIn
   return ret;
 }
 
-/*
- * Class:     ml_dmlc_xgboost4j_java_XGBoostJNI
- * Method:    XGDMatrixSetGroup
- * Signature: (J[I)V
- */
-JNIEXPORT jint JNICALL Java_ml_dmlc_xgboost4j_java_XGBoostJNI_XGDMatrixSetGroup
-  (JNIEnv * jenv, jclass jcls, jlong jhandle, jintArray jarray) {
-  DMatrixHandle handle = (DMatrixHandle) jhandle;
-  jint* array = jenv->GetIntArrayElements(jarray, NULL);
-  bst_ulong len = (bst_ulong)jenv->GetArrayLength(jarray);
-  int ret = XGDMatrixSetGroup(handle, (unsigned int const *)array, len);
-  //release
-  jenv->ReleaseIntArrayElements(jarray, array, 0);
-  return ret;
-}
-
 /*
  * Class:     ml_dmlc_xgboost4j_java_XGBoostJNI
  * Method:    XGDMatrixGetFloatInfo

jvm-packages/xgboost4j/src/native/xgboost4j.h

@@ -95,14 +95,6 @@ JNIEXPORT jint JNICALL Java_ml_dmlc_xgboost4j_java_XGBoostJNI_XGDMatrixSetFloatI
 JNIEXPORT jint JNICALL Java_ml_dmlc_xgboost4j_java_XGBoostJNI_XGDMatrixSetUIntInfo
   (JNIEnv *, jclass, jlong, jstring, jintArray);
 
-/*
- * Class:     ml_dmlc_xgboost4j_java_XGBoostJNI
- * Method:    XGDMatrixSetGroup
- * Signature: (J[I)I
- */
-JNIEXPORT jint JNICALL Java_ml_dmlc_xgboost4j_java_XGBoostJNI_XGDMatrixSetGroup
-  (JNIEnv *, jclass, jlong, jintArray);
-
 /*
  * Class:     ml_dmlc_xgboost4j_java_XGBoostJNI
  * Method:    XGDMatrixGetFloatInfo

python-package/xgboost/core.py

@@ -811,9 +811,7 @@ class DMatrix(object):
         if _use_columnar_initializer(group):
             self.set_interface_info('group', group)
         else:
-            _check_call(_LIB.XGDMatrixSetGroup(self.handle,
+            self.set_uint_info('group', group)
-                                               c_array(ctypes.c_uint, group),
-                                               c_bst_ulong(len(group))))
 
     def get_label(self):
         """Get the label of the DMatrix.

src/c_api/c_api.cc

@@ -725,13 +725,9 @@ XGB_DLL int XGDMatrixSetGroup(DMatrixHandle handle,
                               xgboost::bst_ulong len) {
   API_BEGIN();
   CHECK_HANDLE();
-  auto *pmat = static_cast<std::shared_ptr<DMatrix>*>(handle);
+  LOG(WARNING) << "XGDMatrixSetGroup is deprecated, use `XGDMatrixSetUIntInfo` instead.";
-  MetaInfo& info = pmat->get()->Info();
+  static_cast<std::shared_ptr<DMatrix>*>(handle)
-  info.group_ptr_.resize(len + 1);
+      ->get()->Info().SetInfo("group", group, kUInt32, len);
-  info.group_ptr_[0] = 0;
-  for (uint64_t i = 0; i < len; ++i) {
-    info.group_ptr_[i + 1] = info.group_ptr_[i] + group[i];
-  }
   API_END();
 }