docs: public static DMatrixSparseCSC transpose(DMatrixSparseCSC a , @Nullable DMatrixSparseCSC a_t , @Nullable IGrowArray gw ) {
  
          if( a_t == null ) {
              a_t = new DMatrixSparseCSC(a.numCols,a.numRows,a.nz_length);
          } else {
              a_t.reshape(a.numCols,a.numRows,a.nz_length);
          }
  
          ImplCommonOps_DSCC.transpose(a, a_t, gw);
          return a_t;
      }