I have an array in python with x,y points used to draw a polygon = feasible region. 

```
[[0.0, 10.0], [0.0, 20.0], [10.0, 0.0], [20.0, 0.0]]

```

The problem is, I need the biggest area between the points to be filled. So I need to reorder the array so I'd have the proper order to draw the biggest polygon possible. The order is important as it connects the neighbour points in the array. 
I tried to sort the array by first element ascending, the second descending, but nothing seems to work. 

```
def scatterplot(points):

 points.sort(key=operator.itemgetter(0,1))

 x1 = []
 y1 = []

 for p in range(0,len(points)):
    plt.plot(points[p][0],points[p][1],'go',markersize=10)
    x1.append(points[p][0])
    y1.append(points[p][2])

 plt.fill(x1,y1,'red',alpha=1)
 plt.show()

```

I guess I'm missing something from math here. Any help will be appreciated. Thanks

```
[[0.0, 10.0], [0.0, 20.0], [10.0, 0.0], [20.0, 0.0]]

```

![enter image description here](https://i.stack.imgur.com/iyaai.png)

```
[[0.0, -0.0], [0.0, 4.0], [2.0, 0.0], [1.5, 2.0]]

```

![enter image description here](https://i.stack.imgur.com/14snX.png)