more precise on the documentation
@@ -156,7 +156,8 @@ def spatial_transformer_grid(theta, output_shape, use_cudnn=True):
~chainer.Variable: A variable of shape :math:`(n, 2, h_O, w_O)`.
In the 2nd dimension, the first element is the coordinate along the
x axis, and the second element is the coordinate along the y axis.
- All the coordinates are scaled to fit range :math:`[-1, 1]`.
+ All the coordinates in the image are scaled to fit range
+ :math:`[-1, 1]`.
This means that the coordinate :math:`(-1, -1)` corresponds to
the upper-left corner of the input image.
