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# Polynomial Method:

The ellipse has a major and minor axis. If a_{1} and b_{1}are major and minor axis respectively. The centre of ellipse is (i, j). The value of x will be incremented from i to a_{1}and value of y will be calculated using the following formula

## Drawback of Polynomial Method:

- It requires squaring of values. So floating point calculation is required.
- Routines developed for such calculations are very complex and slow.

## Algorithm:

1. Set the initial variables: a = length of major axis; b = length of minor axis; (h, k) = coordinates of ellipse center; x = 0; i = step; x_{end} = a.

2. Test to determine whether the entire ellipse has been scan-converted. If x>x_{end}, stop.

3. Compute the value of the y coordinate:

4. Plot the four points, found by symmetry, at the current (x, y) coordinates:

Plot (x + h, y + k) Plot (-x + h, -y + k) Plot (-y – h, x + k) Plot (y + h, -x + k)

5. Increment x; x = x + i.

6. Go to step 2.

### Program to draw an Ellipse using Polynomial Method:

**Output:**