add circular option

[FlorentD]

No description provided.

[codecov-io]

Current coverage is 56.83%

Merging #6 into master will increase coverage by +1.39% as of e98a017

@@            master      #6   diff @@
======================================
  Files            8       8       
  Stmts          312     329    +17
  Branches        46      48     +2
  Methods          0       0       
======================================
+ Hit            173     187    +14
- Partial          5       6     +1
- Missed         134     136     +2

Review entire Coverage Diff as of e98a017

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