Checking if a point is in a polygon or circle: is_inside

### 13.16.4 Checking if a point is in a polygon or circle: is_inside

The is_inside command determines whether or not a point is in a polygon or a circle.

- is_inside takes two arguments:
  - P, a point.
  - C, a polygon or a circle.
- is_inside(P,C) returns 1 if P is inside C (including the boundary) and returns 0 otherwise.

#### Examples.

- Input:
  is_inside(0,circle(-1,1))
  Output:

  1

- Input:
  is_inside(2,polygon([1,2-i,3+i]))
  Output:

  1

- Input:
  is_inside(1-i, triangle([1,2-i,3+i]))
  Output:

  0