fix windows run

wrapper/xgboost_wrapper.cpp

@@ -8,7 +8,9 @@
 #include <algorithm>
 // include all std functions
 using namespace std;
-
+#ifdef _MSC_VER
+#define isnan(x) (_isnan(x) != 0)
+#endif
 #include "./xgboost_wrapper.h"
 #include "../src/data.h"
 #include "../src/learner/learner-inl.hpp"
@@ -149,7 +151,7 @@ extern "C"{
                                bst_ulong nrow,
                                bst_ulong ncol,
                                float  missing) {
-    bool nan_missing = std::isnan(missing);
+    bool nan_missing = isnan(missing);
     DMatrixSimple *p_mat = new DMatrixSimple();
     DMatrixSimple &mat = *p_mat;
     mat.info.info.num_row = nrow;
@@ -157,7 +159,7 @@ extern "C"{
     for (bst_ulong i = 0; i < nrow; ++i, data += ncol) {
       bst_ulong nelem = 0;
       for (bst_ulong j = 0; j < ncol; ++j) {
-        if (std::isnan(data[j])) {
+        if (isnan(data[j])) {
           utils::Check(nan_missing, "There are NAN in the matrix, however, you did not set missing=NAN");          
         } else {
           if (nan_missing || data[j] != missing) {