changed copy_rows_fromd_by_idx a bit to make it clearer

1 files changed, 4 insertions, 4 deletions

diff --git a/nerv/doc/nerv_matrix.md b/nerv/doc/nerv_matrix.md
index b915dee..dfd843d 100644
--- a/nerv/doc/nerv_matrix.md
+++ b/nerv/doc/nerv_matrix.md
@@ -63,10 +63,10 @@ Copy the content of a __CuMatrix__ `a` to __Matrix__ `self`, they should be of t
 Copy the content of the __Matrix__ `self` to a __MMatrix__ `a`.
 * __void Matrix.copy_tod(Matrix self, CuMatrix a)__  
 Copy the content of the __Matrix__ `self` to a __CuMatrix__ `a`.
-* __void Matrix.copy_rows_fromh_by_idx(Matrix self, MMatrix ma, MMatrixInt idx)__  
-`idx` should be a row vector. This function copy the rows of `ma` to `self` according to `idx`, in other words, it assigns `ma[idx[i]]` to `self[i]`.
-* __void Matrix.copy_rows_fromd_by_idx(Matrix self, CuMatrix b, CuMatrix idx)__  
-`idx` needs to a row vector matrix, it stacks the rows of index `idx` of the __CuMatrix__ `b` and copies to `self`.
+* __void Matrix.copy_rows_fromh_by_idx(Matrix self, MMatrix ma, MMatrixInt idx, int idx_begin)__  
+`idx` should be a row vector. This function copy the rows of `ma` to `self` according to `idx`, in other words, it assigns `ma[idx[i+idx_begin]]` to `self[i]`.
+* __void Matrix.copy_rows_fromd_by_idx(Matrix self, Matrix b, Matrix idx, int idx_begin)__  
+`idx` needs to a row vector matrix, it stacks the rows of index `idx` of the __CuMatrix__ `b` and copies to `self`. `idx_begin` is used as an offset in the `idx` index array.
 * __void Matrix.update_select_rows(Matrix self, Matrix err, Matrix idx, double alpha, double beta)__  
 Update selected rows of `self`, i.e. `self[idx[i]] = self[idx[i]] * (1 - beta * alpha) + alpha * err[i]`.
 * __void Matrix.add(Matrix self, Matrix ma, Matrix mb, Element_type alpha, Element_type beta)__