message: Edit comment for Circulant.
diff: @@ -160,20 +160,20 @@ class _BaseLinearOperatorCirculant(linear_operator.LinearOperator):
  `block_depth = 1` means `A` is symmetric circulant. For example,
  ```
  - A = |x y z y|
  - |y x y z|
  - |z y x y|
  - |y z y x|
  + A = |w z y x|
  + |x w z y|
  + |y x w z|
  + |z y x w|
  ```
  `block_depth = 2` means `A` is block symmetric circulant with symemtric
  - circulant blocks. For example, with `X`, `Y`, `Z` symmetric circulant,
  + circulant blocks. For example, with `W`, `X`, `Y`, `Z` symmetric circulant,
  ```
  - A = |X Y Z Y|
  - |Y X Y Z|
  - |Z Y X Y|
  - |Y Z Y X|
  + A = |W Z Y X|
  + |X W Z Y|
  + |Y X W Z|
  + |Z Y X W|
  ```
  `block_depth = 3` means `A` is block symmetric circulant with block
  