code: public static int cusparseXcsrgeamNnz(
          cusparseHandle handle, 
          int m, 
          int n, 
          cusparseMatDescr descrA, 
          int nnzA, 
          Pointer csrSortedRowPtrA, 
          Pointer csrSortedColIndA, 
          cusparseMatDescr descrB, 
          int nnzB, 
          Pointer csrSortedRowPtrB, 
          Pointer csrSortedColIndB, 
          cusparseMatDescr descrC, 
          Pointer csrSortedRowPtrC, 
          Pointer nnzTotalDevHostPtr)
      {
          return checkResult(cusparseXcsrgeamNnzNative(handle, m, n, descrA, nnzA, csrSortedRowPtrA, csrSortedColIndA, descrB, nnzB, csrSortedRowPtrB, csrSortedColIndB, descrC, csrSortedRowPtrC, nnzTotalDevHostPtr));
      }
docs: Description: Compute sparse - sparse matrix addition of matrices
  stored in CSR format